Journals >Acta Photonica Sinica
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2014
Volume: 43 Issue 9
41 Article(s)
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Research Article
The Effects of Atmospheric Turbulence on the Orbital Angular Momentum-multiplexed System
ZOU Li, ZHAO Sheng-mei, and WANG Le
The effects of turbulence aberrations on Orbital Angular Momentum (OAM)-multiplexed system by numerical simulation were analysed, where the turbulence aberration was simulated by several random phase screens generated by Kolmogorov model. The performances of normalized-received power and Bit Error Rate(BER) of the OAM-The effects of turbulence aberrations on Orbital Angular Momentum (OAM)-multiplexed system by numerical simulation were analysed, where the turbulence aberration was simulated by several random phase screens generated by Kolmogorov model. The performances of normalized-received power and Bit Error Rate(BER) of the OAM-multiplexed system were characterized through changing the refractive index structure constant C2n and transmission distance z. The results show that normalized-received power decreases and the BER performance increases while the constant C2n and transmission distance z increases. The normalized-received power decreases to less than 0.2 and BER increases to more than 0.3 when the refractive index structure constant C2n is 5×10－13m－2/3. The normalized-received power decreases to less than 0.3 and BER increases to more than 0.35 while transmission distance z reaches 10 000 m. The comparison of the BER performance between two OAM-multiplexed systems with different values of the azimuthal index l is characterized. The results show that the OAM-multiplexed system which has closer values of l is more affected by atmospheric turbulence. At last, the BER with atmospheric tarbulence is decreased by two to three orders of magnitude compared with that one without atmospheric tarbulence at the same OSNR. The researchs have a good reference value for practical application of OAM-multiplexed system..
Acta Photonica Sinica
- Publication Date: Jan. 01, 1900
- Vol. 43, Issue 9, 901001 (2014)
Analysis of Haze-fog Events Based on Laser Ceilometer
BU Ling-bing, YUAN Jing, GAO Ai-zhen, LEI Yong, GUO Wei, GAO Hai-yang, and HUANG Xing-you
To investigate the optical characteristics of haze-fog, sequence diagram of backscattering coefficient, profiles of extinction coefficient, visibility were retrieved from data of laser ceilometer. Combining data from sounding, automatic meteorological station and visibility sensor, analyses of haze-fog process were perTo investigate the optical characteristics of haze-fog, sequence diagram of backscattering coefficient, profiles of extinction coefficient, visibility were retrieved from data of laser ceilometer. Combining data from sounding, automatic meteorological station and visibility sensor, analyses of haze-fog process were performed. The results show that the occurrence of haze-fog is strongly influenced by meteorological elements, static, small wind is benefit to the emergence of the haze, while higher relative humidity which has great influence on visibility often leads to coexist of haze and fog. The fog which often occurs in low altitude has stronger backscattering, large vertical rate of change, while haze often has weaker backscattering, smaller vertical rate of change and larger span in vertical direction; The variation of backscattering coefficient in the fog and haze were analyzed, both horizontal visibility and vertical visibility were obtained from data of ceilometer. The horizontal visibility was consistent with visibility from visibility sensor, and the variation of vertical visibility had opposite trends with relative humidity while has the same trends with wind speed. By analyzing variation of backscattering coefficient with time, the Fourier transform power spectral distribution was obtained, this distribution was corresponding with the border characteristics of fog and haze..
Acta Photonica Sinica
- Publication Date: Jan. 01, 1900
- Vol. 43, Issue 9, 901002 (2014)
Research on Nonsmooth H∞ Control for the Adaptive Optics System
ZHAO Xin, and MA Cai-wen
To design an adaptive optics robust controller with the characteristics of simple structure and low orders, a nonsmooth H∞ control method for the adaptive optics system was proposed.The full order H∞ controller and the reduced order H∞ controller were designed by conventional H∞ control method combined with model reducTo design an adaptive optics robust controller with the characteristics of simple structure and low orders, a nonsmooth H∞ control method for the adaptive optics system was proposed.The full order H∞ controller and the reduced order H∞ controller were designed by conventional H∞ control method combined with model reduction based on Hankel singular values.And the orders of the controllers are 226 and 163 respectively, whereas the nonsmooth H∞ controller designed for the system is simply the product of a constant matrix and a 4 order single input single output transfer function.For the sake of control performance verification and comparation, the dynamic atmospheric turbulence wavefront phase was simulated, as well as the residual wavefront phase corrected by adaptive optics systems with the full order H∞ controller and with the nonsmooth H∞ controller.The simulation demonstrates that the two adaptive optics systems achieve approximate control performance, and proves the efficiency of nonsmooth H∞ control method for the adaptive optics system..
Acta Photonica Sinica
- Publication Date: Jan. 01, 1900
- Vol. 43, Issue 9, 901003 (2014)
The Non-correspondence of Diffraction Patterns of Positive and Negative Grade from Low-frequency Liquid Surface Waves
MIAO Run-cai, MENG Feng, and MA Jing
Based on the acousto-optic diffraction theory, the light diffraction characteristics of low-frequency liquid surface waves was investigated using the method of optical. An expression was given about the non-corresponding orders, the analytical expression was simulated by means of the numerical method, which explains thBased on the acousto-optic diffraction theory, the light diffraction characteristics of low-frequency liquid surface waves was investigated using the method of optical. An expression was given about the non-corresponding orders, the analytical expression was simulated by means of the numerical method, which explains the mechanism of the non-correspondence effect. In experiment, the steady and visible diffraction pattern was observed, and the fringe spacing has obvious asymmetry. With the increasing of incident angle, the distinct non-correspondence of the positive and negative diffraction orders is found. The number of the positive diffraction pattern is more than the negative one. The results show that: the non-correspondence effect is related to the incident angle. With the increasing of incident angle, the non-correspondence effect is more obvious. The negative diffraction order has maximum. For the orders exceeding this value, the negative diffraction pattern disappeared. It shows that the theoretical analysis agrees with the experimental result well..
Acta Photonica Sinica
- Publication Date: Jan. 01, 1900
- Vol. 43, Issue 9, 905001 (2014)
Propagation Dynamics and Vortex Trajectory of an Airy Vortex Beam in Gradient-index Media
CHENG Ke, XIA Ji-shen, and ZHONG Xian-qiong
The analytical expression for the propagation of an Airy vortex beam through a paraxial ABCD optical system was derived and used to study propagation dynamics, Poynting vector and vortex trajectory of an Airy vortex beam in gradient-index (GRIN) media, where the effects of vortex core on the main lobe of Airy beam and The analytical expression for the propagation of an Airy vortex beam through a paraxial ABCD optical system was derived and used to study propagation dynamics, Poynting vector and vortex trajectory of an Airy vortex beam in gradient-index (GRIN) media, where the effects of vortex core on the main lobe of Airy beam and Poynting vector are stressed. The results show that vortex trajectory and ballistic dynamics are no longer conventional parabolic but trigonometric shapes in the GRIN media. Especially, the Airy vortex beam represents singular behavior at propagation distance z=(2j+1)L/4, and the Poynting vector gradually exhibits reversal before and after z=(j+1)L/2. Based on the analysis of ballistic dynamics, the main lobe of Airy beam is overlapped by vortex core at critical distance, as the beam propagates further, it does not only show self-reconstruction due to the self-healing property of the Airy beam, but also exhibit rotating about the closest vortex..
Acta Photonica Sinica
- Publication Date: Jan. 01, 1900
- Vol. 43, Issue 9, 905002 (2014)
MOPA Structured 1 120 nm Yb-doped All Fiber Amplifier
LIU Xiao-juan, FU Sheng-gui, GUO Li-ping, HAN Ke-zhen, and ZHOU Bo-jun
Based on master oscillator power amplifier regime, a 976 nm laser diode pumped 20-m-long single-mode double-clad large-mode-area ytterbium-doped fiber amplifier at 1 120 nm was experimentally demonstrated.In the experiment, the injected power of the fiber seed laser was set to be 10 mW.When the diode laser pump power iBased on master oscillator power amplifier regime, a 976 nm laser diode pumped 20-m-long single-mode double-clad large-mode-area ytterbium-doped fiber amplifier at 1 120 nm was experimentally demonstrated.In the experiment, the injected power of the fiber seed laser was set to be 10 mW.When the diode laser pump power is increased to 1.5 W, the amplifier system begins to emit signal laser at 1 120 nm.The experimental results reveal that the signal output power increases slowly under low pump power level, however, when the pump power is beyond 3.4 W, the slope efficiency increases fleetly to 48.5%.Limited to the available launched pump power of 6.8 W, a maximum output power of 1.97 W is achieved.The total optical-to-optical conversion efficiency of the system is 29%.The measured center wavelength of the output signal laser is 1120.89 nm with a linewidth as narrow as 0.02 nm, which well preserves the characteristics of the seed laser.According to the parameters of the optical devices in the experiment, based on the steady-state-model of the double-cladding fiber amplifier and finite-difference-method, the relationship of the output signal power versus the diode laser pump power is theoretically calculated.The comparison between the experimental results and the theoretical results displays that the growth trend of the output signal laser power kisses well with the theoretical model.The system will be saturated when the pump power beyond 200 W, which reveals that the amplifier has a large space of power scaling up..
Acta Photonica Sinica
- Publication Date: Jan. 01, 1900
- Vol. 43, Issue 9, 906001 (2014)
Sensing Properties of Nickel Electroplating Protected Fiber Bragg Grating Based on Stress Analysis
XIE Jian-feng, WANG Ying, MO Zhao, LIU Yong-song, and ZENG Ren-xian
In order to protect Fiber Bragg Grating (FBG), a non-coarsening fiber surface electroless plating and electroplating technics with good adhesion force between layer and fiber was proposed. Based on stress analysis, the temperature sensitivity of protected FBG was achieved in theory, the stresses on the protected FBG unIn order to protect Fiber Bragg Grating (FBG), a non-coarsening fiber surface electroless plating and electroplating technics with good adhesion force between layer and fiber was proposed. Based on stress analysis, the temperature sensitivity of protected FBG was achieved in theory, the stresses on the protected FBG under varied temperatures were analyzed by a finite element analysis software (ANSYS) and verified by experiment. The results show that the temperature sensitivity of protected FBG is 20.6951 pm/℃ theoretical and 22.076 pm/℃ from the experiments, which the results of theoretical analysis match the ones from experiments and simulations very well. The temperature sensitivity is 2.2 times as much as that of bare FBG. The desirable thickness of metallic protect layer can be obtained and the temperature sensitivity can be improved..
Acta Photonica Sinica
- Publication Date: Jan. 01, 1900
- Vol. 43, Issue 9, 906002 (2014)
Investigation of a Liquid-core Photonic Crystal Fiber with High Birefringence
JIANG Ling-hong, ZHENG Yi, ZHENG Kai, and PENG Ji-ying
A kind of highly birefringent Photont Crystal Fiber (PCF) was proposed, a central defect elliptical hole and two other elliptical holes just below and above the central one were introduced in the core region of PCF. The central defect elliptical air hole was filled with high refractive index of liquid such as carbon diA kind of highly birefringent Photont Crystal Fiber (PCF) was proposed, a central defect elliptical hole and two other elliptical holes just below and above the central one were introduced in the core region of PCF. The central defect elliptical air hole was filled with high refractive index of liquid such as carbon disulfide. The birefringence, power confinement factor, fundament mode field and dispersion characteristic of the fiber were studied by the full-vector finite element method. The results show that the liquid-core PCF has high power confinement factor, the high negative dispersion is realized in a wavelength range from 0.6 to 1.8 μm, and the birefringence up to 6.8×10－2 at 1.55 μm.The proposed PCF has achieved both the high birefrigence and broadband high negative dispersion characteristics, and showes good polarization stability by analyzing stucutural parameter fluctuation..
Acta Photonica Sinica
- Publication Date: Jan. 01, 1900
- Vol. 43, Issue 9, 906003 (2014)
Investigation of Residual Chromatic Dispersion Equalizer in High-speed Optical Coherent Communication Systems
ZHANG Hu, and CHEN Jian
The equalization-enhanced phase noise was introduced when fully using electronic dispersion compensation in high-speed optical coherent communication system. Using electronic dispersion compensation to compensate the residual chromatic dispersion was proposed, to realize the transmission at 100 Gbit/s per specified chaThe equalization-enhanced phase noise was introduced when fully using electronic dispersion compensation in high-speed optical coherent communication system. Using electronic dispersion compensation to compensate the residual chromatic dispersion was proposed, to realize the transmission at 100 Gbit/s per specified channel and beyond on the existing 10 Gbit/s fiber-optic transmission line were realized. By using VPI, the 112 Gbit/s optical coherent system performance with finite impulse response filter and overlap frequency domain equalization filter were compared, which is used to compensate the residual chromatic dispersion.Simulation results indicate that in the same tap length, FIR has more effective residual chromatic dispersion compensation ability than overlap frequency domain equalization.Also, the finite impulse response filter has more stable equalization performance and lower computation complexity, and it is suitable for the hybrid chromatic dispersion compensation..
Acta Photonica Sinica
- Publication Date: Jan. 01, 1900
- Vol. 43, Issue 9, 906004 (2014)
Investigation of FBG Voltage Sensor Based on Joule Heat
MI Lin, YANG De-xing, JIANG Ya-jun, WANG Mei-rong, GUO Yu-ning, and QU Jun-rong
A new type of fiber Bragg grating voltage sensor which is based on joule heat was designed and used to precisely monitor small voltage.In the experiment, a layer of nickel was plated around the grating by vacuum evaporation method and the grating was hermetically packaged in copper tube which is full of aerogel.The cenA new type of fiber Bragg grating voltage sensor which is based on joule heat was designed and used to precisely monitor small voltage.In the experiment, a layer of nickel was plated around the grating by vacuum evaporation method and the grating was hermetically packaged in copper tube which is full of aerogel.The center of reflection spectrum of fiber Bragg grating drifts as the fiber grating heated due to the heat generated in nickel layer when the current goes through.Thus the transformation from voltage change to centre wavelength drift could be obtained.The experiment results show that the direct current voltage sensitivity after packaged is up to 520 pm/V2, and it can be used in the low frequency alternating current sensing.This system owns the advantages of simple structure, high accuracy and easy to be implemented..
Acta Photonica Sinica
- Publication Date: Jan. 01, 1900
- Vol. 43, Issue 9, 906005 (2014)
Measurement of Saturation Point of Aqueous Solution Based on Long Period Michelson Interferometer
ZHANG Bin, ZHU Hao-tian, HE Ru-shuang, TAO Wei-dong, PAN Xue-feng, and DONG Jian-feng
A Long Period Fiber Grating(LPFG) whose period is 400 μm was fabricated by amplitude mask technique. The end of the fiber, which is 6 cm from the LPFG, was coated with Ag. Taking NaClO3 aqueous solution for example with same amount of NaClO3 powder added into the solution by every time, a new device and method for immeA Long Period Fiber Grating(LPFG) whose period is 400 μm was fabricated by amplitude mask technique. The end of the fiber, which is 6 cm from the LPFG, was coated with Ag. Taking NaClO3 aqueous solution for example with same amount of NaClO3 powder added into the solution by every time, a new device and method for immediately calibrating saturation point under a specified ambient temperature was studied. Based on the principle of phase difference and solving the eigen equation of core mode and cladding mode of single-mode fiber, the reflectance spectrum variation of LPFG-Michelson interferometer induced by ambient refractive index change was analyzed. By reference to variation tendancy of wavelength shift value with refractive index change, the change curve of the notch wavelength shift induced was obtained by repeatedly add NaClO3 powder into the solution. The experiment value is fitted by least square method, and the theoretical saturation point of NaClO3 aqueous solution under 32℃ is obtain by solving intersection point of the fitted curves, which the difference between the result and literature is only 1.5%..
Acta Photonica Sinica
- Publication Date: Jan. 01, 1900
- Vol. 43, Issue 9, 906006 (2014)
Spectrum of Dual-wavelength Phase Shift FBG and Its Application in Fiber Sensing
ZHU Xiang, and YANG Yuan-hong
The theoretical model of a dual wavelength phase-shifted fiber Bragg grating was established and its spectral characteristics were obtained by numerical simulations, which pointed that the transmission peaks spacing was affected by the amount of phase shift, refractive index modulation and grating length. The expressioThe theoretical model of a dual wavelength phase-shifted fiber Bragg grating was established and its spectral characteristics were obtained by numerical simulations, which pointed that the transmission peaks spacing was affected by the amount of phase shift, refractive index modulation and grating length. The expression of transmission peaks spacing was acquired by resonance phase conditions of fiber bragg grating Fabry-Perot cavity, and the curves obtained by numerical simulation method accord well with the curves obtained by analytic formula, proves the correctness of the numerical simulation results. Finally, a sensing method based on transmission peaks spacing of a dual wavelength phase-shifted fiber Bragg grating was proposed, the temperature sensing characteristics were analyzed, and the theoretical sensitivity was about 60 pm/℃..
Acta Photonica Sinica
- Publication Date: Jan. 01, 1900
- Vol. 43, Issue 9, 906007 (2014)
Design and Optimize of All-fiber Mode Converter
LU Ju, CHEN Ming-yang, and ZHANG Yong-kang
An all-fiber LP02 broadband mode converter is proposed in this paper. Boardband is achieved when LP01 mode is converted to LP02 mode by using LP11 mode as an intermediate mode based on the mode matching principle and the designed dual-core fiber. The relationship between fiber parameters and the effective index was invAn all-fiber LP02 broadband mode converter is proposed in this paper. Boardband is achieved when LP01 mode is converted to LP02 mode by using LP11 mode as an intermediate mode based on the mode matching principle and the designed dual-core fiber. The relationship between fiber parameters and the effective index was investigated as well as structure parameters and conversion bandwidth, and the structure is optimized by using the beam propagation method and the mode coupling theory. The bandwidth is compared of the method convert LP01 mode to LP02 mode directly with the method using LP11 mode as an intermediate mode. Simulation results show that the intermediate method can improve the bandwidth and conversion bandwidth can reach 121nm with a conversion efficiency over 80%..
Acta Photonica Sinica
- Publication Date: Jan. 01, 1900
- Vol. 43, Issue 9, 906008 (2014)
Airplane Detection in Optical Remote Sensing Image Based on Sparse-Representation
LIN Yu-dong, HE Hong-jie, YIN Zhong-ke, and CHEN Fan
In this paper, an airplane detection algorithm based on sparse representation is proposed to solve the problems of low detection precision in complicated backgrounds and difficult achivement of rotation invariant.Three steps are included in this algorithm:first, a geometrical dictionary is built according to the rigid In this paper, an airplane detection algorithm based on sparse representation is proposed to solve the problems of low detection precision in complicated backgrounds and difficult achivement of rotation invariant.Three steps are included in this algorithm:first, a geometrical dictionary is built according to the rigid property and the typical geometric appearance of the airplane to be detected;second, the optimal combination of the geometrical parts is obtained by solving the airplane profile approximation model set up under the framework of sparse representation theory;third, the object salient map is generated based on the star-structure part-based model and the location of the objects can be obtained from the salient map.Experimental results indicate that this algorithm can adaptively select the geometrical parts of airplane as few as possible and is insusceptible to illumination, color or complicated backgrounds.Compared to existing methods, the detection precision of our algorithm reaches above 90%, and the detection speed is significantly improved..
Acta Photonica Sinica
- Publication Date: Jan. 01, 1900
- Vol. 43, Issue 9, 910001 (2014)
Image Information Encryption by Compressed Sensing and Optical Theory
LU Pei, LIU Xiao-yong, LU Xi, TIAN Min, and CAO Hai-bin
Due to the problem of security for information encryption system, an image information encryption scheme combined compressed sensing with optical theory was proposed. At the transmitted terminal, image information encryption based on compressive sensing was realized by sparse representation and random projection firstlDue to the problem of security for information encryption system, an image information encryption scheme combined compressed sensing with optical theory was proposed. At the transmitted terminal, image information encryption based on compressive sensing was realized by sparse representation and random projection firstly. Then, the measured values with low data volume after dimensional reduction were re-encrypted by double random-phase encoding technique and then dispersed and embedded into the host image. At the received terminal, original image information was reconstructed approximately via Orthogonal Matching Pursuit algorithm after the inverse process of double random-phase encoding technique. Not only the security of information was ensured under the premise of decreasing the amount of data transmission and reducing the size of the random phase masks but also the privacy of keys were assured which were gained by rules rather than transmitted from transmitter to receiver. Numerical experiments showed that the quality of decryption image was ideal with the corresponding peak signal to noise ratio of 30.899 1 dB and this system had the advantages of good performance of anti-cropping, anti-noising, anti-rotating and anti-filtering, strong robustness and high security..
Acta Photonica Sinica
- Publication Date: Jan. 01, 1900
- Vol. 43, Issue 9, 910002 (2014)
Image Denoising Based on Seperable Total Variation Model
HU Liao-lin, WANG Bin, XUE Rui-yang, and WANG Ya-ping
Based on traditional discrete total variation model, we established the separable total variation model exploiting low-dimensional projection; Combining with Frobenius norm and the convexity of image, we proposed a method that rooted in convex optimization to solve the separable discrete total variation problem, which Based on traditional discrete total variation model, we established the separable total variation model exploiting low-dimensional projection; Combining with Frobenius norm and the convexity of image, we proposed a method that rooted in convex optimization to solve the separable discrete total variation problem, which can be applied into image denoising. Simulation results show that, with the ability of effectively keeping profile and details, the peak signal to noise ratio of 256×256 size image after denoising can reach 28.5 dB while the variance of random noise is 0.1, thus illustrating the good performance at the removal of random noise. By revising the numbers of iterations, the relationship between speed and accuracy can be balanced with considerable flexibility, thus adjusting to different denoising requirements..
Acta Photonica Sinica
- Publication Date: Jan. 01, 1900
- Vol. 43, Issue 9, 910003 (2014)
Recognition Technology of Large-Scale Hybrid-Distortion Target
REN Bing, MA Jun, LAN Lan, and WANG Wen-sheng
In this paper, area-polar algorithm is firstly proposed to solve the problem of hybrid-distortion target recognition technology. This method makes area transform and polar coordinate transform for both target and template, based on the surjective function relationship between the scale and the area of similar figures aIn this paper, area-polar algorithm is firstly proposed to solve the problem of hybrid-distortion target recognition technology. This method makes area transform and polar coordinate transform for both target and template, based on the surjective function relationship between the scale and the area of similar figures and the invariance of rotation of polar coordinate. Applied on hybrid optoelectronic joint transform correlator, a combined method can achieve large-scale hybrid-distortion target recognition, which includes area-polar algorithm and edge extracting process based on morphological dilation.Presented with examples of planes, The optical correlation experiments show that this method can enhance the brightness of the correlation peaks for hybrid-distortion target, which possesses large hybrid-distortion tolerance(with 0°~100° rotation distortion tolerance and 100%~200% scale distortion tolerance), and expands the scope of target recognition. The hybrid-distortion target recognition capability by this method is better than by Log-polar transform algorithm, and also better than by synthetic discriminant function and by derivative methods, besides its time complexity is far less than synthetic discriminant function′s and derivative methods′..
Acta Photonica Sinica
- Publication Date: Jan. 01, 1900
- Vol. 43, Issue 9, 910004 (2014)
Interference Characteristics of Vortex Beams and Its Application in Deformation Measurement
[in Chinese], [in Chinese], [in Chinese], and [in Chinese]
Out-of-plane displacement of deformation object can be measured by application of vortex beams in electronic speckle pattern interferometry. The deformation measurement was based on the combination of traditional electronic speckle interferometry techniques and liquid crystal spatial light modulators. The vortex beams Out-of-plane displacement of deformation object can be measured by application of vortex beams in electronic speckle pattern interferometry. The deformation measurement was based on the combination of traditional electronic speckle interferometry techniques and liquid crystal spatial light modulators. The vortex beams which were generated by liquid crystal spatial light modulator can be used as reference light or object light. When the vortex beam as reference light and plane beam as object light, or the interference intensity was calculated, and the interference fringe patterns were simulated before and after the tested object deformed. The deformed interference fringe patterns were analyzed and the corresponding phase-maps were calculated though phase shifting method. The three-dimensional phase distribution of simulation is coincident with the theoretical value of out-of-plane displacement. The results show that the vortex beam can be used in out-of-plane displacement measurement, which provides a new method in deformation measurement..
Acta Photonica Sinica
- Publication Date: Jan. 01, 1900
- Vol. 43, Issue 9, 912001 (2014)
Simultaneous Measurement of the Degree of Polarization and Spatial Analysis of Depolarization Based on a Rochon Prism
LUO Yun-han, WANG Fang, GE Jing-hua, CHEN Zhe, TANG Jie-yuan, YU Jian-hui, LU Hui-hui, ZHANG Jun, LIU Hong-huan, and SUI Zhan
Spatial averaged depolarization requires that depolarized light beam not only has a low degree of polarization(DOP), and also avoids the polarization state exhibiting continuous band in spatial distribution.To achieve the measurement of the DOP of the beam and observation of the degree of spatial depolarization, a methSpatial averaged depolarization requires that depolarized light beam not only has a low degree of polarization(DOP), and also avoids the polarization state exhibiting continuous band in spatial distribution.To achieve the measurement of the DOP of the beam and observation of the degree of spatial depolarization, a method based on the Rochon prism was proposed.The dependence of the DOP on each optical power measurements was firstly deduced, following with experimental measurement and comparison to full polarization test method.The relative deviation in the DOP for the same light beam, 0.192%, shows the two methods have the same performance in measurement of DOP.However, the feature of the proposed method separating o component and e component in the space enable observations of the spatial distribution of polarization states respectively.The Rochon prism based method will play an important role in simultaneous measurement of DOP and observance of spatial polarization distribution..
Acta Photonica Sinica
- Publication Date: Jan. 01, 1900
- Vol. 43, Issue 9, 912002 (2014)
A Non-contact Method for Determining Junction Temperature of LED Based on the Relative Spectral Difference
RAO Feng, XU An-cheng, and ZHU Xi-fang
A method for determining AlGaInP-based LED junction temperature was developed based on the relative spectral difference. The relative spectra of different LED with various drive currents and substrate temperatures were measured by spectrometer, and the differences of LED relative spectra were calculated. And then the lA method for determining AlGaInP-based LED junction temperature was developed based on the relative spectral difference. The relative spectra of different LED with various drive currents and substrate temperatures were measured by spectrometer, and the differences of LED relative spectra were calculated. And then the linearity of the relative spectral differences and junction temperatures was analyzed. At last, the acurracy of the proposed method was compared with the peak wavelength method. The results show good positive correlation between relative spectral difference and junction temperatue. The acurrucy and the error of the proposed method become worse as the bandwith of spectrometer increases. The acurrucy of proposed method with the spectrometer of 2 nm bandwith is much higher than the peak wavelenght method of 1 nm bandwith. While the propose method of 5 nm bandwith has the same acurrucy with the peak wavelenght method of 1 nm bandwith..
Acta Photonica Sinica
- Publication Date: Jan. 01, 1900
- Vol. 43, Issue 9, 912003 (2014)
Extracting Moiré Fringe Deviation with Tunnel-exploring Algorithm
SUN Tao, and SONG Yi-zhong
In order to accurately extract out Moiré fringe deviations, the tunnel-exploring algorithm was proposed, and used to analyze Moiré patterns.The Moiré patterns were produced with double Ronchi gratings, and captured in many projecting directions.With the technology processing digital images, the experimenIn order to accurately extract out Moiré fringe deviations, the tunnel-exploring algorithm was proposed, and used to analyze Moiré patterns.The Moiré patterns were produced with double Ronchi gratings, and captured in many projecting directions.With the technology processing digital images, the experiment Moiré patterns were tracked and further analyzed with a series of analyzing techniques.This series of processing algorithms are called tunnel-exploring algorithm here.The tunnel-exploring algorithm includes tracking maximums of fringes, excavating fringe tunnels, binarizing Moiré patterns, filtering out noise, exploring fringe tunnels, extracting the track of tunnel extension, and so on.First, each of Moiré fringes is tracked based on its column pixels′ maximums.According to the maximums′ distributions, the fringes are excavated into tunnels.Each trenched width, viz.the width of pixels, is adjusted to make the tunnel link up, but not to interfere the adjacent fringes.Second, the Moiré patterns with excavated tunnels are binarized and filtered.The fringe tunnels are smoothed out by filtering out the noise on both sides of each tunnel.Last, the fringe tunnels are explored based on the distributions of both sides of each tunnel, and the track of each tunnel extension are extracted out, then the fringes′ deviations are obtained.Therefore, by tunnel-exploring algorithm processing, the fringes′ deviations were obtained.Then, they are used to reconstruct a section temperature distribution of the flow field using nonlinear auto-adjusting iterative reconstruction technique.As the result, the highest temperature reconstructed is 492℃.The rated surface temperature of the heater is about 500℃.The reconstructed section is just above the heater, so the reconstruction is considered reasonable..
Acta Photonica Sinica
- Publication Date: Jan. 01, 1900
- Vol. 43, Issue 9, 912004 (2014)
The Differential Detection Method of the Symmetric Surface Plasmon Resonance Sensing Structure Excited by FEMI Planar Waveguide
YANG Hai-ma, LIU Jin, YANG Hui, and KONG Ping
In order to improve the detection sensitivity, the method of dual-wavelength differential detection is used. To realize the measured refractive index range being adjustable, a novel surface plasmon resonance sensing structure is described, which consists of a planar waveguide and a symmetric structure with metal-sampleIn order to improve the detection sensitivity, the method of dual-wavelength differential detection is used. To realize the measured refractive index range being adjustable, a novel surface plasmon resonance sensing structure is described, which consists of a planar waveguide and a symmetric structure with metal-sample-metal layer. The mode characteristic of the symmetric structure is analyzed. When the surface plasmon wave is excited, the relationship between the tested refractive index and the dielectric thickness, and the dual-wavelength differential method are researched. Planar waveguides are prepared by the ion-exchange and the graded-index distribution can be fitted by the Fermi function. In experiments Glycerin solutions with the refractive index range of 1.33-1.428 are used for detection by intensity method. Methods of single wavelength and dual-wavelength based on the symmetric structure are used respectively, then the plasmon surface wave can be excited. The refractive index matching condition of this structure can be adjusted through the thickness of the sample, so the tested range is adjustable. If the measured range is appropriate, a linear relationship between normalized intensity and refractive index can be obtained. Theoretical analysis and experimental results show that the sensitivity of the differential detection method is nearly doubled compared with the single-wavelength method..
Acta Photonica Sinica
- Publication Date: Jan. 01, 1900
- Vol. 43, Issue 9, 912005 (2014)
High-precision Phase-shift Laser Range Finder System Based on Laser Beat-frequency
JIANG Cheng-hao, YANG Jin-hua, ZHANG Li-juan, and WANG Xiao-kun
A high-dynamic and high-precision ranging system based on laser phase-shift ranging was studied.The optical frequency modulation technology was introduced in system to realize laser beat-frequency, produce high-frequency modulation signals and complete the rapid-change measuring tape modulation of signal.In the phase dA high-dynamic and high-precision ranging system based on laser phase-shift ranging was studied.The optical frequency modulation technology was introduced in system to realize laser beat-frequency, produce high-frequency modulation signals and complete the rapid-change measuring tape modulation of signal.In the phase demodulation of echo signal, the windowless all-phase spectrum analysis was adopted and the phase calculation of measuring signal was realized for the purpose of reducing the phase demodulation deviation.The calculation shows that the proposed method can effectively retrain spectrum leakage, reduce the influence of noise on the measurement results, and improve the phase demodulation precision.The experiment shows that this ranging system can effectively solve the problems such as poor anti-jamming capability and difficult mitigation of range ambiguity in the phase ranging.The ranging precision is more than 0.5 mm when the modulating signal frequency is 100 MHz and SNR is 30 dB..
Acta Photonica Sinica
- Publication Date: Jan. 01, 1900
- Vol. 43, Issue 9, 912006 (2014)
The Surface Flaws Inspection of Optical Components Based on the Fringe Reflection
ZHAO Wen-chuan, ZHONG Xian-yun, and LIU Bin
A method for the optical surface flaws inspection based on the fringe reflection was proposed. The test system is composed of the liquid crystal display, CCD camera and a computer. The intensity-modulated patterns are generated on the screens on both the horizontal and vertical respectively. The CCD records the patternA method for the optical surface flaws inspection based on the fringe reflection was proposed. The test system is composed of the liquid crystal display, CCD camera and a computer. The intensity-modulated patterns are generated on the screens on both the horizontal and vertical respectively. The CCD records the pattern images via the tested surface. The phase and amplitude modulation are calculated by the phase-shift technique. The flaws location can be got from the fringe contrast. Also the height of the flaws can be gained by integration from the phase change caused by the flaws. This method is simple and cheap. Compared with other techniques, this technique can get the three dimension information of the flaws. The experimental results have confirmed the feasibility of this method..
Acta Photonica Sinica
- Publication Date: Jan. 01, 1900
- Vol. 43, Issue 9, 912007 (2014)
Non-threshold Windowed Fourier Filter Algorithm
LI Xing-long, LI Feng, ZHAO Ran, and SUN Ping
In order to reduce the speckle noise in phase distribution of deformation, a non-threshold windowed Fourier filter algorithm was proposed.The maximal amplitude of stripe frequency is set as the filtering criterion by scanning the amplitude of stripe frequency in the window, which the optimum frequency image is obtainedIn order to reduce the speckle noise in phase distribution of deformation, a non-threshold windowed Fourier filter algorithm was proposed.The maximal amplitude of stripe frequency is set as the filtering criterion by scanning the amplitude of stripe frequency in the window, which the optimum frequency image is obtained and the threshold window is not set in the window Fourier filter algorithm. And the proposed algorithm is used on the fringe patterns. Experiment results show that the proposed algorithm have a better performance in reducing the speckle noise and a high precision in phase calculation. The algorithm proposed can be used to filter other images as a low-pass filter..
Acta Photonica Sinica
- Publication Date: Jan. 01, 1900
- Vol. 43, Issue 9, 912008 (2014)
Study of Scattering Characters of Coated Non-spherical Aerosols Particles and its Effects on the Laser Signals Propagation
LI Hua, WANG Yan-bin, ZOU Qian-jin, QI Feng-jie, WANG Min, and HUANG Cheng-gong
Based on the characters of aerosols′ generation and evolution in partial areas, the morphology characters of the coated axisymmetric, non-spherical aerosols particles with typical symmetrical structure were studied.A T-matrix method to calculate the coated aerosols particles′ scattering characters was introduced to theBased on the characters of aerosols′ generation and evolution in partial areas, the morphology characters of the coated axisymmetric, non-spherical aerosols particles with typical symmetrical structure were studied.A T-matrix method to calculate the coated aerosols particles′ scattering characters was introduced to the calculation of the scattered characters of a non-spherical particle coated by an ellipsoidal particle.As an example, the two typical distributions of the coated aerosols′ scattering phase function were provided in propagation of laser wavelength 1 064 nm.The results were applied to the multi-scattering phenomena in laser signal propagations through dense aerosols, with the use of the Monte Carlo ray tracing method in the scattering and the applications of laser signals′ breadth calculation in atmosphere.Because of the multi-scattering, the laser signals′ pulse width enlarged 3 μs and 4 μs corresponding to distance 3 km and 5 km.At last, it was pointed out that the aerosols′ scattered characters are influenced by the morphology characters, typical size, chemical components, the densities of the particles etc., the aerosols′ scattered characters influence obviously on the laser signal′s atmosphere propagation in dense aerosols..
Acta Photonica Sinica
- Publication Date: Jan. 01, 1900
- Vol. 43, Issue 9, 914001 (2014)
2D Calculation of Heating Process and Crater Shape for Ultrashort Lasers Ablation Silicon Films
JIN Fang-yuan, CHEN Bo, E Shu-lin, and WANG Hai-feng
Based on two-temperature model and free-electron gas model, a new calculation method, finite element model is fabricated, which provides a new perspective into studying the energy transport process in silicon film irradiated by ultrashort laser pulses.By choosing suitable thickness of silicon films, the 2D spatial and Based on two-temperature model and free-electron gas model, a new calculation method, finite element model is fabricated, which provides a new perspective into studying the energy transport process in silicon film irradiated by ultrashort laser pulses.By choosing suitable thickness of silicon films, the 2D spatial and temporal evolutions of the electron temperature as well as carrier density in silicon film irradiated by IR and visible lasers are obtained.The evolutions of complex refractive index and plasma reflectivity are also calculated, through analysis, results show that they are dominated by carrier density.By depicting the electron heat flux evolutions, the energy transport process is analyzed.The distributions of lattice and carrier density are depicted, results show that the lattice temperature is stayed well down below the melting point, and the critical density of carrier density is the dominated factor of ablation.The calculated threshold fluences are validated by comparing study and experimental data.The predicted crater shapes are obtained, which are waiting for experimental validating..
Acta Photonica Sinica
- Publication Date: Jan. 01, 1900
- Vol. 43, Issue 9, 914002 (2014)
Influences of Laser Pulse Energy on Physical Characteristics of Laser-induced Aluminum Alloy Plasma
ZHENG Pei-chao, LIU Hong-di, WANG Jin-mei, YU Bin, YANG Rui, ZHANG Bin, and WANG Xiao-meng
In order to investigate the influences of laser pulse energy on the radiation characteristics and the expansion process of laser-induced plasma, the fast images of laser-induced aluminum alloy plasma were obtained by ICCD camera under different laser pulse energy, and the electron temperature and electron number densitIn order to investigate the influences of laser pulse energy on the radiation characteristics and the expansion process of laser-induced plasma, the fast images of laser-induced aluminum alloy plasma were obtained by ICCD camera under different laser pulse energy, and the electron temperature and electron number density with different laser pulse energy were also determined by using the Boltzmann plot method and Stark broadening of line, respectively. The results show that the plasma presents an obvious hierarchical structure, and the excitation threshold of the plasma is approximate 3 mJ. The areas of different regions in plasma present different characteristics with different laser pulse energy. There is no significant hierarchical structure when the laser pulse energy is under 10 mJ. The electron temperature increases from 4 980 K to 7 221 K, and the electron number density which is of the order of 1017 cm－3 increases firstly and then trends to saturation when the laser pulse energy increases from 10 mJ to 100 mJ..
Acta Photonica Sinica
- Publication Date: Jan. 01, 1900
- Vol. 43, Issue 9, 914003 (2014)
Stabilizing the Optical Parametric Oscillator Cavity by Fringe-locking Technique in Preparation of Squeezed State of Light
QU Wen-yan, SONG Jia-zheng, FENG Fei, XUE Yu-lang, and ZHANG Tong-yi
A fringe-locking technique was employed to stabilize the optical parametric oscillator cavity, which would be affected by external environmental disturbance, such as vibration and airflow.First, how the locking point influence the squeezing degree was analyzed theoretically, the results show that position at half of thA fringe-locking technique was employed to stabilize the optical parametric oscillator cavity, which would be affected by external environmental disturbance, such as vibration and airflow.First, how the locking point influence the squeezing degree was analyzed theoretically, the results show that position at half of the transmission peak could be the best locking point.Then the fringe-locking technique was applied to achieve the resonance between the optical parametric oscillator cavity and the injected infrared light experimentally.The experimental results show that the length variance of the cavity in continuous operation over 2 h is 7.27 nm and the longest locking time is 3.8 h, which is sufficient for the detection of the squeezed states of light..
Acta Photonica Sinica
- Publication Date: Jan. 01, 1900
- Vol. 43, Issue 9, 914004 (2014)
The Preparation of Graphene Based Broadband Saturable Absorber and Its Application in Laser
XU Xiang, JIANG Man, LI Diao, CHEN Hao-wei, QI Mei, ZHANG Jing-hang, REN Zhao-yu, and BAI Jin-tao
Graphene was used for broadband saturable absorber and simultaneously applied in 1.06 μm Nd∶YAG laser, 2 μm Tm∶YAP laser and 1.55 μm Erbium-doped fiber laser. Taking advantage of the Atmospheric-pressure chemical vapor deposition method, acetylene and 25 μm thickness copper foil were applied as the carbon source and thGraphene was used for broadband saturable absorber and simultaneously applied in 1.06 μm Nd∶YAG laser, 2 μm Tm∶YAP laser and 1.55 μm Erbium-doped fiber laser. Taking advantage of the Atmospheric-pressure chemical vapor deposition method, acetylene and 25 μm thickness copper foil were applied as the carbon source and the catalyst respectively. Keeping them growing at the atmosphere of 1 000 ℃ and ordinary atmospheric pressure. In the experiment of 1.06 μm Nd∶YAG solid state laser, the repetition frequency is 360 kHz when the output power is 10 W. The shortest pulse duration is 240 ns and the single pulse energy is about 27 μJ, corresponding peak power is 115.7 W. In the experiment of 2 μm Tm∶YAP solid state laser, a LD centered at 795 nm wavelength is employed for pump source. The pulse light is output via an end mirror with 10% transmittance, which generate the shortest Q-switching pulse with 1.4 μs pulse width. In the experiment of 1.55 μm erbium-doped ring cavity all fiber laser, a 1.25 m Erbium(Er3+) doped fiber is used for gain medium. The average mode-locking laser output power is 10 mW when pump power reach 100 mW. The output pulse duration and repetition frequency are about 314 ps and 20 MHz respectively. Therefore, the broadband saturable absorption of graphene was demonstrated, and stable short pulse laser was obtained in a series of experiments..
Acta Photonica Sinica
- Publication Date: Jan. 01, 1900
- Vol. 43, Issue 9, 914005 (2014)
The Design of Reflective Scanning Device for Drilling the Inverted Cone Micro-hole with Femtosecond Laser Pulses
ZHAO Hua-long, ZHOU Ren-kui, ZHAO Wei, YANG Xiao-jun, LI Ming, and JIA Hai-ni
Based on the Dove Prism scanning principle, a reflective scanning device was designed which was driven by high speed rotating motor and composed of three reflectors in K glyph configuration. The scanning device can be used for the femtosecond laser high-precision spiral drilling system and the accuracy is insensitive tBased on the Dove Prism scanning principle, a reflective scanning device was designed which was driven by high speed rotating motor and composed of three reflectors in K glyph configuration. The scanning device can be used for the femtosecond laser high-precision spiral drilling system and the accuracy is insensitive to the laser beam quality. The drilling scanning speed is twice as the motor speed with high drilling efficiency. Compared with Dove Prism System, the scanning device is easy to assemble and can avoid the pulse width broadening phenomenon of femtosecond laser. The tests show that it can accomplish high effective drilling the inverted cone micro holes whose diameters are between 0.05 mm and 0.2 mm with the machining accuracy less than ±2 μm..
Acta Photonica Sinica
- Publication Date: Jan. 01, 1900
- Vol. 43, Issue 9, 914006 (2014)
Mode Properties of Hybrid Plasmonic Waveguide with an Metal Nano-rib
WANG Cong, WU Gen-zhu, ZHOU Pei, ZHANG Meng, and CHEN Da-ru
A novel hybrid plasmonic waveguide which consists of a semiconductor nanowire and a mental nano-rib was proposed based on the traditional hybrid plasmonic waveguide.Relationship between the geometrical sizes and the properties of the proposed hybrid plasmonic waveguide, such as effective refractive index, propagation lA novel hybrid plasmonic waveguide which consists of a semiconductor nanowire and a mental nano-rib was proposed based on the traditional hybrid plasmonic waveguide.Relationship between the geometrical sizes and the properties of the proposed hybrid plasmonic waveguide, such as effective refractive index, propagation loss and normalized mode area was numerically simulated by employing a finite element method.And the gain threshold of the hybrid waveguide was analyzed.Simulation results reveal that this kind of hybrid waveguide has a low propagation loss and high field confinement ability, and its minimum mode area is only 0.001 52 μm2..
Acta Photonica Sinica
- Publication Date: Jan. 01, 1900
- Vol. 43, Issue 9, 916001 (2014)
Preparation and Characterization of Fe3O4@SiO2@CdTe Fluorescent Magnetic Microspheres
ZHANG Li-song, WANG Gong-zheng, MO Run-Yang, YE Ming, and LI Xiao-Meng
Monodisperse Fe3O4@SiO2@CdTe magnetic and luminescent double functional composite microsphere were successfully prepared by amide condensation reaction with Fe3O4 magnetic nanoparticles coated by SiO2 with －NH2, which were got by hydrolyzing with (3-ammonium propyl) triethoxy silane and CdTe quantum dots modified by thMonodisperse Fe3O4@SiO2@CdTe magnetic and luminescent double functional composite microsphere were successfully prepared by amide condensation reaction with Fe3O4 magnetic nanoparticles coated by SiO2 with －NH2, which were got by hydrolyzing with (3-ammonium propyl) triethoxy silane and CdTe quantum dots modified by thioglycolic acid. Fe3O4 magnetic nanoparticles were received by hydrothermal synthesis method and stber method. The structures and properties of the composite microsphere were characterized by transmission electron microscopy, X-ray diffraction, fluorescence spectrophotometer and vibrating sample magnetometer. The results demonstrated that Fe3O4@SiO2@CdTe magnetic and luminescent composite microspheres have good monodispersity, the average particles size is 470 nm and the saturation magnetization is 37.9 emu/g. The submicron magnetic and luminescent composite particles have well superparamagnetism and high efficiency fluorescent light..
Acta Photonica Sinica
- Publication Date: Jan. 01, 1900
- Vol. 43, Issue 9, 916002 (2014)
Multiple-valued Characteristic Research of Nonlinear One-dimensional Photonic Crystal Reflection Spectrum
ZHANG Rong-jun, ZHANG Juan, and XIA Rui-shen
Based on the sublayer division and backward recursion algorithm, a simple and efficient numerical method for calculating the nonlinear reflection spectrum of one-dimensional photonic crystal with one kerr nonlinear defect layer was presented.The nonlinear reflection spectrum in the wavelength range of 1 535 nm to 1 565Based on the sublayer division and backward recursion algorithm, a simple and efficient numerical method for calculating the nonlinear reflection spectrum of one-dimensional photonic crystal with one kerr nonlinear defect layer was presented.The nonlinear reflection spectrum in the wavelength range of 1 535 nm to 1 565 nm was obtained by the method.When incident intensity is higher than the threshold, the defect mode moves slowly and appears inclined curved multiple-valued features at certain wavelengths.The influence of incident intensity on jump-up wavelength and jump-down wavelength was analyzed.The influence of parameters of periodic dielectric layer and nonlinear layer on reflection spectrum were investigated systematically.The results showed that the period, high-low refractive index ratio of periodic medium and the thickness of nonlinear defect layer is increased, the defect mode width is narrowed and the threshold of incident intensity, jump-on and jump-down wavelength is decreased.While when the third-order nonlinear coefficient is increased for nonlinear layer, the threshold of incident intensity is decreased and the defect mode width, jump-on and jump-down wavelength threshold is not changed obviously.The multiple-valued feature has an important role in the design of optical switch, optical filter, et al..
Acta Photonica Sinica
- Publication Date: Jan. 01, 1900
- Vol. 43, Issue 9, 923001 (2014)
A MIM Surface Plasmon T-splitter Based on a Stub Structure
JIANG Ya-lan, WANG Ji-cheng, WANG Yue-ke, LIU Hong-jiao, LIU Cheng, and GAO Shu-mei
A T-shaped splitter of the surface plasmon waveguide with a stub based on metal-insulator-metal structure was proposed. The relationship between transmission and structure parameters was investigated by Finite-difference time-domain method. The simulation results show that the periodical changes of surface plasmons powA T-shaped splitter of the surface plasmon waveguide with a stub based on metal-insulator-metal structure was proposed. The relationship between transmission and structure parameters was investigated by Finite-difference time-domain method. The simulation results show that the periodical changes of surface plasmons power can be achieved by changing the width and length of stub structure in T-shaped waveguide. Also, the periodical changes of splitting ratio for changes of surface plasmons can be obtained by changing the stub structure position of the output port in the metal-insulator-me waveguide structure. When the splitting ratio get maximum(or minimum), T-shaped splitter can achieve the unidirectional propagation of changes of surface plasmons. Besides, the periodical changes of splitting ratio was explained based on the changes of surface plasmons interference theory..
Acta Photonica Sinica
- Publication Date: Jan. 01, 1900
- Vol. 43, Issue 9, 923002 (2014)
A Polymer Dispersed Liquid Crystal Fresnel Zone Plate
HE Ru-shuang, ZHANG Bin, WANG Zhen-yu, TAO Wei-dong, PAN Xue-fen, and DONG Jian-feng
A wave band ring pattern was fabricated by femtosecond laser on a glass substrate which was plated with aluminum, the wavelength of the laser was 800 nm, and the width of pulse was 130 fs. The solvent system phase separation preparation was used to manufacture a polymer dispersed liquid crystal Fresnel zone plate. By tA wave band ring pattern was fabricated by femtosecond laser on a glass substrate which was plated with aluminum, the wavelength of the laser was 800 nm, and the width of pulse was 130 fs. The solvent system phase separation preparation was used to manufacture a polymer dispersed liquid crystal Fresnel zone plate. By the He-Ne laser, the properties of the zone plate was tested. The results show that the sample has good photoelectric regulation properties with the increasing voltage, the intensity of the focal point is able to be adjusted. Meanwhile, along the direction of optical axis, the difference between the location of the main focal point and its theoretical value is less than 5％, and the diffraction efficiency of the polymer dispersed liquid crystal Fresnel zone plate is 10.4% with the voltage is 160 V, which is close to the theoretical value of 12.1％. The results prove this design to be feasible..
Acta Photonica Sinica
- Publication Date: Jan. 01, 1900
- Vol. 43, Issue 9, 923003 (2014)
Nonclassical Property and Decoherence of Photon-added Chaotic Field
LU Dao-Ming
Photon-added chaotic field is constructed by creation operator roling in chaotic field.Nonclassical property and decoherence of photon-added chaotic field are analysed.Master equations of density operators can be concisely solved by the technique of integration with in an ordered product of operators and virtue of therPhoton-added chaotic field is constructed by creation operator roling in chaotic field.Nonclassical property and decoherence of photon-added chaotic field are analysed.Master equations of density operators can be concisely solved by the technique of integration with in an ordered product of operators and virtue of thermo-entangled state representation.We get the evolution formula of the field density operator which is in photon-added chaotic field initially.The evolutions of its Wigner function and the evolutions of P representation are given.The nonclassical property is discussed by calculating its Wigner function in phase space.Numerical results show that the photon-added chaotic field displays nonclassical property initially, and its nonclassical property is weakened with dissipation time increasing.On the other hand, its nonclassical property is also weakened with added photon number increasing..
Acta Photonica Sinica
- Publication Date: Jan. 01, 1900
- Vol. 43, Issue 9, 927001 (2014)
Controlled Quantum Information Sharing of An Arbitrary One-particle State via Cluster State
LI Yan-ping, WANG Tian-yin, and YIN Bao-yin
Based on the strong persistency of entanglement of cluster state, two quantum sharing schemes were presented to realize the controlled teleportation of an arbitrarily one-particle using a four-particle cluster state as the quantum channel. In the first scheme, the sender Alice, controller Charlie and receiver Bob shareBased on the strong persistency of entanglement of cluster state, two quantum sharing schemes were presented to realize the controlled teleportation of an arbitrarily one-particle using a four-particle cluster state as the quantum channel. In the first scheme, the sender Alice, controller Charlie and receiver Bob share a four-particle cluster entangled state. Firstly Alice performs a three-particle joint Von-Neumann measurement on her qubits. Then Charlie performs a quantum measurement on his qubit with Z basis. Finally Bob can reconstruct the shared single particle by doing unitary transformation according to the measured results from Charlie and Bob. In the second scheme, three parties also shared a four-particle cluster state and an auxiliary particle, Alice and Charlie only need Bell state measurements and Bob can get the transmitted state by performing a swap bit flip operation and one unitary transformation. Compared with the existing schemes, the success probability of these both schemes are 100% and the proposed schemes only need 4-particle cluster state as the quantum channel. Furthermore, the proposed schemes can be implemented under the current laboratory techniques..
Acta Photonica Sinica
- Publication Date: Jan. 01, 1900
- Vol. 43, Issue 9, 927002 (2014)
Quantitative Investigation on the Changes of Optical Property Parameters by Using DMSO and Thiazone as Enhancers for Optical Clearing of Porcine Skin in Vitro
JIANG Jing-ying, CHEN Wei, MA Cong-cong, and XU Ke-xin
The relationship between optical property parameters and the change of hyperosmotic agents were evaluated. Porcine skins, medicated without and with biocompatible hyperosmotic agents-dimethyl sulfoxide and thiazone, were measured by FT-IR spectrophotometer and double-integrating-spheres system. Optical property parametThe relationship between optical property parameters and the change of hyperosmotic agents were evaluated. Porcine skins, medicated without and with biocompatible hyperosmotic agents-dimethyl sulfoxide and thiazone, were measured by FT-IR spectrophotometer and double-integrating-spheres system. Optical property parameters of samples were calculated by inverse adding-doubling modeling method. The results demonstrated that with the course of the penetration of biocompatible hyperosmotic agents into porcine skin tissue, optical property parameters(absorption coefficient and scattering coefficient)of tissue samples have got decrease obviously along with the depth of light penetrating into tissue increased. In conclusion, the optical property parameters of bio-tissues could be changed by use of both agents, furthermore, thiazone has led to the better clearing than dimethyl sulfoxide..
Acta Photonica Sinica
- Publication Date: Jan. 01, 1900
- Vol. 43, Issue 9, 930001 (2014)
Slag Quantitative Analysis Based on PLS Model by Laser-induced Breakdown Spectroscpy
CHEN Xing-long, DONG Feng-zhong, WANG Jing-ge, NI Zhi-bo, HE Wen-gan, FU Hong-bo, and XU Jun
On-line quantitative analysis of slag, which could greatly improve product quality and reduce energy consumption, is a highly demanded technique in metallurgic industry.Laser induced breakdown spectroscopy combined partial least squares regression model was proposed to determine the content of CaO, MgO, Al2O3 and Fe inOn-line quantitative analysis of slag, which could greatly improve product quality and reduce energy consumption, is a highly demanded technique in metallurgic industry.Laser induced breakdown spectroscopy combined partial least squares regression model was proposed to determine the content of CaO, MgO, Al2O3 and Fe in slag.Background correction and spectral normalization, which used plasma intensity as reference signal, were applied to improve spectral signal stability.5 slag samples were analyzed by using the partial least squares regression model established with 25 slag elements-known samples.The mean prediction relative error of CaO, MgO, Al2O3 and Fe was 4.7%、11.5%、17.9% and 12.5%, respectively.The experimental results indicate that laser-induced breakdown spectroscopy combined PLS is a potential tool for on-line quantitative analysis of slag..
Acta Photonica Sinica
- Publication Date: Jan. 01, 1900
- Vol. 43, Issue 9, 930002 (2014)
Influence of Protein and Carbohydrate in Maize Leaf by Infection of Maize Southern Rust Using FTIR
SHI You-ming, LI Dong-yu, LIU Gang, and YI Shi-lai
In order to study biochemical parameters of maize leaf, which infected by maize southern rust, Fourier transform infrared spectroscopy was applied to obtain the spectra of infection and normal maize leaves. The characteristic region and fingerprint region at spectrum were selected to study the change of protein and carIn order to study biochemical parameters of maize leaf, which infected by maize southern rust, Fourier transform infrared spectroscopy was applied to obtain the spectra of infection and normal maize leaves. The characteristic region and fingerprint region at spectrum were selected to study the change of protein and carbohydrate in maize leaf. Compared infection with normal leaf spectrum, amide bands had diversification obviously, the change of absorption band of carbohydrate was not prominence. It showed that the protein secondary structures had changed, and the diversification of carbohydrate in infection leaf was not obviously. Curve-fitting analysis of wave number at 1 800~1 480 presented the sheet and helix in protein secondary structures was decrease in infected leaf, and the turn structure was increase at the infected initial stage. The random coil structure was increase rapidly at infected end stage, this structure was absent at infected initial stage and normal maize leaves. The results show that Fourier transform infrared spectroscopy combine with curve-fitting analysis can be used to explore the change of biochemical parameters in infection maize leaf, which provides evidence for studying the disease resistance of maize..
Acta Photonica Sinica
- Publication Date: Jan. 01, 1900
- Vol. 43, Issue 9, 930003 (2014)
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