Journals >Chinese Journal of Quantum Electronics
Contents
2006
Volume: 23 Issue 5
32 Article(s)
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Research Article
Progress in the study of high birefringence polarization maintained photonic crystal fibers
Ya-ni ZHANG, Li-yong REN, Li-li WANG, and Run-cai MIAO
The coming out of photonic crystal fibers makes the research of polarization maintained photonic crystal fibers become a hotspot in the field of optical communication. Based on summarizing large numbers of research documents about PM-PCFs in domestic and aboard,the light propagation mechanism and polarization maintainiThe coming out of photonic crystal fibers makes the research of polarization maintained photonic crystal fibers become a hotspot in the field of optical communication. Based on summarizing large numbers of research documents about PM-PCFs in domestic and aboard,the light propagation mechanism and polarization maintaining principles of high birefringence PM-PCFs are analyzed. Furthermore,various design schemes are presented. Finally,the present progress,applications,and foreground of development are put forward..
Chinese Journal of Quantum Electronics
- Publication Date: Oct. 12, 2021
- Vol. 23, Issue 5, 577 (2006)
Manipulation and control of cold neutral molecules and its recent progress
Jian-ping YIN
The basic concepts and principles,experimental schemes and results as well as recent progress of manipulation and control of cold neutral molecules and their geometric moleculeoptical devices in the world are introduced. These contents mainly include: electrostatic guide of cold polar molecules and its molecular pipe,lThe basic concepts and principles,experimental schemes and results as well as recent progress of manipulation and control of cold neutral molecules and their geometric moleculeoptical devices in the world are introduced. These contents mainly include: electrostatic guide of cold polar molecules and its molecular pipe,laser deflection(refraction)of neutral molecules and its molecular prism,laser focusing of neutral molecules and its molecular lens,electrostatic and magnetic reflection of neutral molecules and its molecular mirror,and laser rotation manipulation of cold molecules and its optical centrifuge,and so on..
Chinese Journal of Quantum Electronics
- Publication Date: Oct. 12, 2021
- Vol. 23, Issue 5, 583 (2006)
Small moving target recognition based on multi-feature fusion
Yang YONG, Jing-Ru WANG, and Qi-heng ZHANG
Recognition algorithms for small moving target in strong noise based on single feature has a high false alarm. Sometimes the features of target and noise are very alike. A new recognition algorithm of small moving target based on multi-feature fusion is presented. The reliability and the extraction method of the continRecognition algorithms for small moving target in strong noise based on single feature has a high false alarm. Sometimes the features of target and noise are very alike. A new recognition algorithm of small moving target based on multi-feature fusion is presented. The reliability and the extraction method of the continuous correlation,area and centroid position of the small moving target are analyzed. The normalized features are used to construct robust combined feature that can present the real target based on the multi-feature fusion method. The candidate target with the largest value of fusion feature as the real target is determined. The comparison with recognition method based on only one feature proved that the recognition based on multi-feature fusion could exactly recognize the small moving target..
Chinese Journal of Quantum Electronics
- Publication Date: Oct. 12, 2021
- Vol. 23, Issue 5, 594 (2006)
Study on the effects of chirped laser pulse on the coherent population transfer and autoionization
Li-qiang WANG, Xin-wei ZHA, Guo-fang SHI, Jian SHI, and Xiang-mei ZENG
The high laser intensity is needed in traditional photoionization which shows intensive Rabi oscillations of population. The using of chirped laser pulse can restrain the R,abi oscillations and realize high efficiency of photoionization. This idea should be useful in the study of coherent transfer of population.The high laser intensity is needed in traditional photoionization which shows intensive Rabi oscillations of population. The using of chirped laser pulse can restrain the R,abi oscillations and realize high efficiency of photoionization. This idea should be useful in the study of coherent transfer of population..
Chinese Journal of Quantum Electronics
- Publication Date: Oct. 12, 2021
- Vol. 23, Issue 5, 599 (2006)
Three-body collisions in cesium vapour in the presence of buffer gas
Qiang-hua YUAN, Gang-tai ZHANG, Bao-xia MU, Shu-ying WANG, Xiu-hua CUI, Kang DAI, and Yi-fan SHEN
An experimental study of energy transfer collisions,Cs(6P)+Cs(6S)+He→Cs(5D)+Cs(6S)+He,at thermal energies,was carried out in a cell. Atoms were excited to the 6P3/2 state using a single-mode diode laser. The Cs(6P)atom density and spatial distribution were mapped by monitoring the absorption of a counter-propagating laAn experimental study of energy transfer collisions,Cs(6P)+Cs(6S)+He→Cs(5D)+Cs(6S)+He,at thermal energies,was carried out in a cell. Atoms were excited to the 6P3/2 state using a single-mode diode laser. The Cs(6P)atom density and spatial distribution were mapped by monitoring the absorption of a counter-propagating laser beam. The buffer gas enhanced the energy transfer between Cs(6P)and Cs(6S),which was based on the measurement of the fluorescence from the 7D state populated by the Cs(6P)/Cs(5D)collisions. Since the 5D→6P fluorescence(3.0～3.6μm)can not be detected with this experiment,the rate coefficient has been measured relative to the known rate coefficient of the collision(i.e.,6P+5D→6S+7D). The three-body collision rate coefficient [k3 =(2.2±1.1)×10－28cm6s－1]is obtained..
Chinese Journal of Quantum Electronics
- Publication Date: Oct. 12, 2021
- Vol. 23, Issue 5, 603 (2006)
Spectroscopic properties and thermal stability of erbium-based Bi2O3-B2O3-Ga2O3 glass
Qiu-hua NIE, Haoquan LI, Tie-feng XU, Cheng JIANG, and Xiang SHEN
Some glasses with Er3+-doped Bi2O3-B2O3-Ga2O3 glasses were prepared. The absorption spectra,fluorescence spectra,fluorescence lifetime of4I13/2 level and thermal stability were measured. The intensity parameters were calculated using Judd-Ofelt theory,and the stimulated emission cross sections of the Er3+ ion 4I13/2→4ISome glasses with Er3+-doped Bi2O3-B2O3-Ga2O3 glasses were prepared. The absorption spectra,fluorescence spectra,fluorescence lifetime of4I13/2 level and thermal stability were measured. The intensity parameters were calculated using Judd-Ofelt theory,and the stimulated emission cross sections of the Er3+ ion 4I13/2→4I15/2 transition were calculated using the McCumber theory. The results show that FWHM,σe and fluorescence lifetime have a peak value when contenting 8% mol Ga2O3 in the glass. The maximal FHWM reaches 81 nm and the peak value of σe reaches 1.03×10－20cm2. Meanwhile the thermal stability is also improved with the increase of Ga2O3. The Bi2O3-B2O3-Ga2O3 glass has some excellent optical properties and beneficial for EDFA to realize high gain,low noise and broadband..
Chinese Journal of Quantum Electronics
- Publication Date: Oct. 12, 2021
- Vol. 23, Issue 5, 607 (2006)
Study on recurrent light scattering in random laser with coherent feedback
Fang-zheng FU, and Feng ZHONG
Cao proposed that recurrent light scattering(multiple scattering forming close loop)results in the random laser with coherent feedback. She hasn't indicated the lasing relative probability of the close loops which are formed by different numbers scattering particles. For simplicity a model is proposed,in which ZnO Cao proposed that recurrent light scattering(multiple scattering forming close loop)results in the random laser with coherent feedback. She hasn't indicated the lasing relative probability of the close loops which are formed by different numbers scattering particles. For simplicity a model is proposed,in which ZnO scattering particle is cube and the only one of six surfaces is mirror. For the random laser with coherent feedback arising in laser dye solution containing ZnO nanoparticles or arising in ZnO powder film,according to the analysis and calculation,it is showed that the lasing is much easier to arise in the two-particle closed loop path than in the three-particle closed loop path,and the lasing is more difficult to arise in the closed loop path which contains more particles. The result is agreement with the experiments..
Chinese Journal of Quantum Electronics
- Publication Date: Oct. 12, 2021
- Vol. 23, Issue 5, 613 (2006)
Analyses of radial acoustic waves resonance in CuBr laser discharge tube
Tao MA
A simple model of acoustic oscillations was presented for the CuBr laser discharge tube. An analytical expression of the radial acoustic waves was given. The relation between natural frequency and pulse recurrence frequency was described. It was also found that the acoustic oscillations leads to a redistribution of theA simple model of acoustic oscillations was presented for the CuBr laser discharge tube. An analytical expression of the radial acoustic waves was given. The relation between natural frequency and pulse recurrence frequency was described. It was also found that the acoustic oscillations leads to a redistribution of the density of the active medium in the discharge tube,and this results in a resonant dependence of the average laser output power on the pulse recurrence frequency..
Chinese Journal of Quantum Electronics
- Publication Date: Oct. 12, 2021
- Vol. 23, Issue 5, 617 (2006)
Realization of two-atom quantum controlled phase gate with high efficiency via cavity QED
Xiao-qin SU
Any quantum computation can be simplified to a gate sequence. But the quantum computation is carried out by a certain physical system. We propose here a scheme to carry out two-atom quantum controlled phase gate through cavity QED. In our scheme,the atomic transition is largely detuned with the cavity mode of interest,Any quantum computation can be simplified to a gate sequence. But the quantum computation is carried out by a certain physical system. We propose here a scheme to carry out two-atom quantum controlled phase gate through cavity QED. In our scheme,the atomic transition is largely detuned with the cavity mode of interest,so the atomic spontaneous emission loss is strongly suppressed,and this leads to the enhancement of probability of gate operation. But fidelity is decided by constants α,β,γ,The numerical calculation based on current experimental technology shows that our scheme has high gate fidelity,the average value of fidelity ■=0.982318.That scheme can be realized by experiment..
Chinese Journal of Quantum Electronics
- Publication Date: Oct. 12, 2021
- Vol. 23, Issue 5, 621 (2006)
Geometric phase of a spin-1/2 particle driven by decohering quantum in adiabatic and nonadiatic evolution
Xue-hua YI, Wen RUAN, Xiao-guang YU, and Feng-lan FU
Quantum computer takes advantages from properties of superposition and entanglement,which are also very fragile and easy to be error. But they may be destroyed easily by a process called decoherence. Therefore,how to overcome the effect of decoherence is key to implement quantum computer. Using the no-jump trajectory,BQuantum computer takes advantages from properties of superposition and entanglement,which are also very fragile and easy to be error. But they may be destroyed easily by a process called decoherence. Therefore,how to overcome the effect of decoherence is key to implement quantum computer. Using the no-jump trajectory,Berry's and AA's formula for geometric phase,we calculate the geometric phase of a spin-1/2 system driven by one and two mode quantum fields subject to decoherence in the adiabatic and nonadiabatic case,respectively. By quantum jump method,we find that the corrections to its phase for the no-jump trajectory are different when considering adiabatic and nonadiabatic evolutions. Finally,we discuss the implications of our results from fundamental and quantum computational points..
Chinese Journal of Quantum Electronics
- Publication Date: Oct. 12, 2021
- Vol. 23, Issue 5, 628 (2006)
Quantum mechanical problem for two ions in a Paul trap
Yun-wen WU, and Wen-hua HAI
By use of the well-known truncating series method,A program for calculating the Schr?dinger exact solutions of quantum gate by two ions confined in a linear Paul trap is presented. The lower energy's state function for center of mass is analyzed. Probability distributing grawing is given. We calculate quantum stateBy use of the well-known truncating series method,A program for calculating the Schr?dinger exact solutions of quantum gate by two ions confined in a linear Paul trap is presented. The lower energy's state function for center of mass is analyzed. Probability distributing grawing is given. We calculate quantum state of variance in relatively position △r2＞ h/2 and quantum state of variance in relatively momentum △p2＜ h/2,the variance in position and momentum given by the Heisenberg uncertainty principle △r·△p＞h/2.It is a condition for squeezed states. We conclude that with center of mass in ground state,the quantum states of two ions in relatively position are squeezed states,and the quantum state of two ions is an entanglement state. Uncertainty of quantum measurement and entanglement must be consider in experiment..
Chinese Journal of Quantum Electronics
- Publication Date: Oct. 12, 2021
- Vol. 23, Issue 5, 634 (2006)
Squeezing properties in a system of entangled atoms interacting with optical field of Schr dinger cat state
Tang-kun LIU
The squeezing properties of a light-atom interacting system are studied by means of quantum theory. In the system,two two-level atoms are initially in an entangled state,and the coherent optical field is in a Schrodinger cat state. Influence of the strength of optical field and the phase angle of the coherent states onThe squeezing properties of a light-atom interacting system are studied by means of quantum theory. In the system,two two-level atoms are initially in an entangled state,and the coherent optical field is in a Schrodinger cat state. Influence of the strength of optical field and the phase angle of the coherent states on the double atoms dipole squeezing and the optical field amplitude squeezing are discussed by numerical calculations. It is found that under weak optical field condition,the optical field amplitude squeezing of even coherent state and Yurke-Stoler coherent state interacting with entangled state of atoms is no existence,but the optical field amplitude squeezing of odd coherent states is existence. In the same condition,the double atomic dipole squeezing of even coherent states interacting with entangled state of atoms is no existence,but the double atomic dipole squeezing of odd coherent state and Yurke-Stoler coherent state is existence. Under strong optical field condition,two squeezing phenomenon is no existence..
Chinese Journal of Quantum Electronics
- Publication Date: Oct. 12, 2021
- Vol. 23, Issue 5, 641 (2006)
Quantum entanglement in the interaction between squeezing vacuum state field and moving two-level atom
Ming-sheng ZENG, Fang-sen XIE, and Hui-ming JIANG
The properties of the entanglement between squeezing vacuum state field and moving two-level atom are investigated by using the von Neumann entropy. The influences of field-mode structure of moving two-level atom and the squeezing degree of initial squeezing vacuum state field on the entanglement of the quantum system The properties of the entanglement between squeezing vacuum state field and moving two-level atom are investigated by using the von Neumann entropy. The influences of field-mode structure of moving two-level atom and the squeezing degree of initial squeezing vacuum state field on the entanglement of the quantum system are discussed. The results show that atomic movement can result in evolution periodically of the degree of entanglement. The quantum state will be maximally entangled state for a long time when the squeezing degree are high,the increase of field-mode structure result in more disentangled states..
Chinese Journal of Quantum Electronics
- Publication Date: Oct. 12, 2021
- Vol. 23, Issue 5, 647 (2006)
Time evolution of mesoscopic RLC circuit under a alternating voltage source
Qing LIU, Jing OU YANG, ju HU Ju, Shi-hua CAI, Qiu-ying MIN, and Dan ZOU
The mesoscopic RLC circuit with a alternationg voltage source was discussed by quantum invariant theory. The mutual-couple energe and the dissipation were also taken into account. The Hamiltonian of the mesoscopic system was derived from Lagrangian function. The wave function of the system will evolve to a squeezed staThe mesoscopic RLC circuit with a alternationg voltage source was discussed by quantum invariant theory. The mutual-couple energe and the dissipation were also taken into account. The Hamiltonian of the mesoscopic system was derived from Lagrangian function. The wave function of the system will evolve to a squeezed state as time elapses. In conclusion,the state of the system will evolve from a arbitrary initial state to a general squeezed state..
Chinese Journal of Quantum Electronics
- Publication Date: Oct. 12, 2021
- Vol. 23, Issue 5, 652 (2006)
Dynamical properties of three-mode field interacting with M-type four-level atom
Yong-ping LI
The dynamical properties of three-mode field interacting with M-type four-level atom is studied by means of quantum theory. The influences of detuning,initial photon number and atom initial state are discussed.The dynamical properties of three-mode field interacting with M-type four-level atom is studied by means of quantum theory. The influences of detuning,initial photon number and atom initial state are discussed..
Chinese Journal of Quantum Electronics
- Publication Date: Oct. 12, 2021
- Vol. 23, Issue 5, 659 (2006)
Research on polaritons in photonic crystal with absorptive type of dispersive medium's layer
Gen-ying YAN, Xian-ming YANG, Tian-bao YU, Zhe SHI, and Qing-hua LIAO
The transfer matrix,which represents the dispersive medium's layer,can be rigorously obtained by using Lorentz model and considering boundary conditions. The detailed investigation on polaritons in a symmetric photonic crystal with absorptive type of dispersive medium's layer is presented by adjusting parameterThe transfer matrix,which represents the dispersive medium's layer,can be rigorously obtained by using Lorentz model and considering boundary conditions. The detailed investigation on polaritons in a symmetric photonic crystal with absorptive type of dispersive medium's layer is presented by adjusting parameters of the dispersive medium's layer. It's found that the absorptive type of dispersive cavity and reinforced dispersive cavity may demonstrate similar properties in normal modes coupling,the homogeneous broadening effect,and the detuning effect. But there exists evident differences in transmitted intensity and frequency shift. Finally,the optical bistability in one-dimensional symmetric photonic crystal both with absorptive type of dispersive medium's layer and with Kerr nonlinear layer is also investigated. It's found that optical bistability threshold of the photonic crystal with dispersive medium layer is a little lower than that of structure without dispersive medium layer..
Chinese Journal of Quantum Electronics
- Publication Date: Oct. 12, 2021
- Vol. 23, Issue 5, 665 (2006)
Defects in three-dimensional photonic crystal
Yi ZHANG, and Qi WANG
Transmission property of a FCC structure three-dimensional photonic crystal was studied by transfer matrix method. The transmission properties of the photonic crystal with a point-defect,a line-defect and a plane-defect respectively were mainly analyzed. The defect model will appear when a defect exists in the photonicTransmission property of a FCC structure three-dimensional photonic crystal was studied by transfer matrix method. The transmission properties of the photonic crystal with a point-defect,a line-defect and a plane-defect respectively were mainly analyzed. The defect model will appear when a defect exists in the photonic crystal. The correlation between the defect property and its permittivity ε,radius γ,location was obtained. These conclusions are beneficial to designing optical communication devices such as photonic crystal WDM filters and photonic crystal waveguide..
Chinese Journal of Quantum Electronics
- Publication Date: Oct. 12, 2021
- Vol. 23, Issue 5, 671 (2006)
Projective synchronization in chaotic systems based on observer
Guo-hui LI, and Xiao-nan SUN
Based on state-observer,projective synchronization in a general class of chaotic system is studied,where the corresponding variables between the drive system and the response system are proportional. From the stability of the system,the controller is derived through the pole placement technique by designing the state-oBased on state-observer,projective synchronization in a general class of chaotic system is studied,where the corresponding variables between the drive system and the response system are proportional. From the stability of the system,the controller is derived through the pole placement technique by designing the state-observer of the drive system. The projective synchronization could be realized in a general class of discrete systems. It allows us to arbitrarily amplify or reduce the scale via a feedback control on the slave system in controlling chaos. It is shown that the phase space of response system can be expanded or compressed flexibly as demanded by adjusting the scaling factor arbitrarily. This property makes it potentially useful in secure communication. In addition,the Henon map and the hyperchaotic generalized Henon map are used to show the rightness of the theoretical analysis..
Chinese Journal of Quantum Electronics
- Publication Date: Oct. 12, 2021
- Vol. 23, Issue 5, 677 (2006)
Study on generation and synchronization of 3-scroll chaotic attractors
Fa-qiang WANG, and Chong-xin LIU
The symbolic function is used to generate the 3-scroll chaotic attractors,and the largest Lyapunov exponent,power spectrum,Poincare map are given. Based on Lyapunov stability theory and method of unilateral synchronization,the sufficient conditions for selfsynchronization of the 3-scroll chaotic attractors are derived.The symbolic function is used to generate the 3-scroll chaotic attractors,and the largest Lyapunov exponent,power spectrum,Poincare map are given. Based on Lyapunov stability theory and method of unilateral synchronization,the sufficient conditions for selfsynchronization of the 3-scroll chaotic attractors are derived. Finally,the simulation results of generation and synchronization of 3-scroll chaotic attractors are also given..
Chinese Journal of Quantum Electronics
- Publication Date: Oct. 12, 2021
- Vol. 23, Issue 5, 681 (2006)
Numerical study on effective nonlinear optical properties of metal particle composite films
Yan DENG, Pei WANG, Dou-guo ZHANG, Lin TANG, Xiao-jin JIAO, and Hai MING
The nonlinear decoupling approximation is used to calculate numerically the effective linear dielectric function and third order nonlinear effect of metal particle composite media as function of random volume fraction,especially the high volume fraction,which show the nonlinear optimum volume ratio. The optical nonlineThe nonlinear decoupling approximation is used to calculate numerically the effective linear dielectric function and third order nonlinear effect of metal particle composite media as function of random volume fraction,especially the high volume fraction,which show the nonlinear optimum volume ratio. The optical nonlinearity of composite media as functions of the frequency of the incident light under different volume fraction have been studied. It is found that near the surface plasmon resonance,optical nonlinearity increases when volume fraction inereases to certain value and then decrease due to the influence of the particle-particle interaction to the local field..
Chinese Journal of Quantum Electronics
- Publication Date: Oct. 12, 2021
- Vol. 23, Issue 5, 687 (2006)
Supercontinuum generation in two holey microstructure fibers pumped by femtosecond pulses
Xue-peng SONG, Jian-fei LIN, Bo CHEN, Xia ZHANG, Yong-qing HUANG, and Xiao-min REN
It is reported that supercontinuum spectrums can be generated in two holey microstructure fibers launched by the 20 fs laser pulse train from a Ti:sapphire laser oscillator.Broadband continua extending from 420 to 980 are obtained in the microstructure with.random air lines. It is found that not only MF with periodicalIt is reported that supercontinuum spectrums can be generated in two holey microstructure fibers launched by the 20 fs laser pulse train from a Ti:sapphire laser oscillator.Broadband continua extending from 420 to 980 are obtained in the microstructure with.random air lines. It is found that not only MF with periodical air lines but also MF with random air lines can be used to generate supercontinuum. Analysis indicates that smaller effective mode area and higher nonlinear coefficient are propitious to the supercontinuum generation..
Chinese Journal of Quantum Electronics
- Publication Date: Oct. 12, 2021
- Vol. 23, Issue 5, 692 (2006)
Analysis of the laser beam through random atmosphere channel
Zong-heng YUAN, and Wen-tao ZHANG
In free space optical communication system,the characteristics of atmosphere are very important. These effects include absorption and dispersion of aerosol,dust,frog,rain and haze when laser beam propagates through atmosphere. The laser power attenuation by the absorption and dispersion is introduced. Then the turbulenIn free space optical communication system,the characteristics of atmosphere are very important. These effects include absorption and dispersion of aerosol,dust,frog,rain and haze when laser beam propagates through atmosphere. The laser power attenuation by the absorption and dispersion is introduced. Then the turbulence and its influence of flicker,bend and abruption are analyzed. At last the experimental system and the test method are given. The experiments are carried out in the different air condition at the same time in a day,in different time at the same day and in different visibility condition. The results are in accordance with theoretical analysis..
Chinese Journal of Quantum Electronics
- Publication Date: Oct. 12, 2021
- Vol. 23, Issue 5, 696 (2006)
Research on signal generator in phase-shift laser range-finder based on FPGA
Nin ZHAO, Ji LI, Yi ZHANG, Jun QI, Bi-hai TU, and Hui NIA
A new signal generation method for phase laser ranging finder is proposed based on direct digital synthesizer technology of FPG A. We present the design of hardware and software of the system. The results of experiments proved that the SNR is more than 60dB. Compared with other technologies,it has higher stable frequenA new signal generation method for phase laser ranging finder is proposed based on direct digital synthesizer technology of FPG A. We present the design of hardware and software of the system. The results of experiments proved that the SNR is more than 60dB. Compared with other technologies,it has higher stable frequency,frequency switch rate and lower power consume..
Chinese Journal of Quantum Electronics
- Publication Date: Oct. 12, 2021
- Vol. 23, Issue 5, 701 (2006)
Detection of atmospheric pollutants by direct analysis of inteferogram
Ming-peng SHEN, Yong-hua FANG, Ye HUANG, Wei XIONG, Tian-ge LAN, Da-ming DONG, and Da-cheng LI
A signal processing method was presented to make atmospheric pollutants be detected by mobile passive Fourier transform infrared interferometer. The methodology allows customized digital filters remove information from the interferogram except that associate with frequencies characteristic of a target chemical species A signal processing method was presented to make atmospheric pollutants be detected by mobile passive Fourier transform infrared interferometer. The methodology allows customized digital filters remove information from the interferogram except that associate with frequencies characteristic of a target chemical species of interest. The results indicate that the method is credible for detecting pollutants. The detection of atmospheric pollutants by mobile passive Fourier transform infrared interferometer can be realized easily because spectral backgrounds are not needed..
Chinese Journal of Quantum Electronics
- Publication Date: Oct. 12, 2021
- Vol. 23, Issue 5, 707 (2006)
Research on wavelength of medical CO2 laser
Dan HUANG, Zhong-chen YE, Kun DU, Yu SUN, and Yue-shun YE
From the medical application of laser,there is problem that the wavelength of CO2 laser is not in the vicinity of 10.6μm. By theoretic investigation and experimental study,it is demonstrated that there are diversified wavelengths of CO2 laser from 9 μm to 11 μm. Advices are given for controling the laser wavelength of From the medical application of laser,there is problem that the wavelength of CO2 laser is not in the vicinity of 10.6μm. By theoretic investigation and experimental study,it is demonstrated that there are diversified wavelengths of CO2 laser from 9 μm to 11 μm. Advices are given for controling the laser wavelength of CO2 laser treating instruments..
Chinese Journal of Quantum Electronics
- Publication Date: Oct. 12, 2021
- Vol. 23, Issue 5, 711 (2006)
Studies on phase separation in AlGaIn quaternary alloys
Kun HUANG, Guang-han FAN, Song-hao LIU, Shu-ti LI, and Zhi-you GUO
Group-III-nitride quaternary alloys are useful for blue high brightness light emitting devices and high-temperature,high-power,and high-frequency electronic devices. It is possible to change only the value of the band gap while keeping the lattice parameter at a constant value. The thermodynamical stability of these alGroup-III-nitride quaternary alloys are useful for blue high brightness light emitting devices and high-temperature,high-power,and high-frequency electronic devices. It is possible to change only the value of the band gap while keeping the lattice parameter at a constant value. The thermodynamical stability of these alloys is obtained analytically using the valence force field(VFF)model for wurtzite structures. The unstable two-phase regions for AlxGayIn1－x－yN quaternary alloys are calculated,and the formation of In-rich regions are studied with respects to In-In affinity. The calculated results can provide useful guidance in epitaxial growth of AlGaInN on GaN..
Chinese Journal of Quantum Electronics
- Publication Date: Oct. 12, 2021
- Vol. 23, Issue 5, 714 (2006)
Guided modes in a thin dielectric film symmetrically bounded by left-haned media
Xing-lin WANG, Qi WANG, Jie-long SHI, and Ming SHEN
For linear TE electromagnetic plane waves propagating in a conventional waveguide bounded by symmetrical left-handed media,the guide modes are discussed in detail by looking for the intersections of curves,which are determined by the boundary conditions. The results prove that both fast waves and slow waves can propagaFor linear TE electromagnetic plane waves propagating in a conventional waveguide bounded by symmetrical left-handed media,the guide modes are discussed in detail by looking for the intersections of curves,which are determined by the boundary conditions. The results prove that both fast waves and slow waves can propagate in this peculiar waveguide system,and the relevant properties of the waves are quite different from which in conventional waveguide and left-handed waveguide. The frequency dispersion and group velocity are also considered. Base on the analysis,it can be concluded that this waveguide can support both forward linear TE waves and backward linear TE waves under certain conditions..
Chinese Journal of Quantum Electronics
- Publication Date: Oct. 12, 2021
- Vol. 23, Issue 5, 719 (2006)
Transmission spectra characteristics of phase-shifted long-period fiber gratings and apodized optimization
De-fa WANG, Jie-long SHI, Yuan-yuan CHEN, and Guan-qun CHEN
Based on the coupled-mode theory,the transfer-matrix method is used to calculate the transmission spectra of π phase-shifted long-period fiber gratings(LPFG). It is found that multi-π-phase-shifted LPFG is a filter with two stopbands and one passband,and the pass band width increases with number of π phase shift. IndexBased on the coupled-mode theory,the transfer-matrix method is used to calculate the transmission spectra of π phase-shifted long-period fiber gratings(LPFG). It is found that multi-π-phase-shifted LPFG is a filter with two stopbands and one passband,and the pass band width increases with number of π phase shift. Index apodization method and a new length apodization method are used to optimize the transmission spectra of phase-shifted LPFGs. And the easily realization of the new length apodization method can facilitate the fabrication of phase-shifted LPFG..
Chinese Journal of Quantum Electronics
- Publication Date: Oct. 12, 2021
- Vol. 23, Issue 5, 725 (2006)
Indices automatism tracking system for measurement of atmospheric coherence length
Peng HE, Kui LI, Qing LI, and Jian-ye WANG
Atmospheric coherence length is one of important parameters of atmospheric turbulence,atmospheric propagation of laser and phase adjustment of adaptive optics. Because whole-air or finitied length measurement of atmospheric coherence length uses stars,object in high altitude balloon and the like movement object as indiAtmospheric coherence length is one of important parameters of atmospheric turbulence,atmospheric propagation of laser and phase adjustment of adaptive optics. Because whole-air or finitied length measurement of atmospheric coherence length uses stars,object in high altitude balloon and the like movement object as indices luminous source,the tracking ability is bad. So we devoloped a suit of automatism tracking system. All kinds of atmospheric coherence length automatism measurement can be realized. Atmospheric coherence length measurement ability is improved greatly..
Chinese Journal of Quantum Electronics
- Publication Date: Oct. 12, 2021
- Vol. 23, Issue 5, 731 (2006)
Measurement of total atmospheric spectral transmittance by solar irradiance
Rui-peng GUO, Jie ZMAN, and Rui-zhong RAO
The facility and theory for measuring atmospheric spectral transmittance by solar irradiance were analyzed. An instrument system for atmospheric optical properties measurement was developed. The solar spectral irradiance was acquired by using a flat field and imaging concave grating and a linear CCD. The real time atmoThe facility and theory for measuring atmospheric spectral transmittance by solar irradiance were analyzed. An instrument system for atmospheric optical properties measurement was developed. The solar spectral irradiance was acquired by using a flat field and imaging concave grating and a linear CCD. The real time atmospheric spectral transmittance with the variable of wavelength band was obtained by employing a specific calibration method,and it can represent the molecular absorption effects on atmospheric radiation. The results were validated by comparing them with other instrument..
Chinese Journal of Quantum Electronics
- Publication Date: Oct. 12, 2021
- Vol. 23, Issue 5, 736 (2006)
Measurements of optical turbulence in duct
Yu JIANG, Zong-yong ZENG, He-lai LIU, Jian-guo LIU, and Wen-qing LIU
The spectrum of temperature fluctuations was measured by micro-temperature and outer scale was obtained in duct. The results detector in duct. The distribution of C(2,n)and out scale was obtained in duct. The results of measurement show that some temperature spectra accord with von Karman's law in duct. The distribThe spectrum of temperature fluctuations was measured by micro-temperature and outer scale was obtained in duct. The results detector in duct. The distribution of C(2,n)and out scale was obtained in duct. The results of measurement show that some temperature spectra accord with von Karman's law in duct. The distribution of C(2,n)are given in duct. In the end,outer scale has little variety in duct.Therefore,managing the average of the wind speed,we must have taken into account the effect on the path weighting function by the distribution of C(2,n). Scintillation coming from refractive index fluctuations is more less than the measurement of scintillation in fact. Temperature fluctuations are not main source in scintillation in duct..
Chinese Journal of Quantum Electronics
- Publication Date: Oct. 12, 2021
- Vol. 23, Issue 5, 741 (2006)
A simple statistical algorithm for the estimation of MODIS spectral reflectance
Shang-pei XUN, Wen-yun WU, and Hong-qun ZHANG
By applying the proposed algorithms and associated processing code,MODIS radiance of channel 1 to 7 are corrected for atmospheric effects to generate the surface reflectance product. A simple statistical algorithm for the estimation of MODIS spectral reflectance is developed based on the statistics of MODIS surface refBy applying the proposed algorithms and associated processing code,MODIS radiance of channel 1 to 7 are corrected for atmospheric effects to generate the surface reflectance product. A simple statistical algorithm for the estimation of MODIS spectral reflectance is developed based on the statistics of MODIS surface reflectance and the radiance at the top of atmosphere. The algorithm is validated by comparing with ground-based measurements. The suitability and limitation of the proposed method are discussed..
Chinese Journal of Quantum Electronics
- Publication Date: Oct. 12, 2021
- Vol. 23, Issue 5, 746 (2006)
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