Journals >Frontiers of Optoelectronics
Contents
2010
Volume: 5 Issue 4
13 Article(s)
Export citation format
Research Article
Flower-like CuO hierarchical nanostructures: synthesis, characterization, and property
Jiarui HUANG, Feng TANG, Cuiping GU, Chengcheng SHI, and Muheng ZHAI
Nanoflake-based flower-like CuO nanostructures have been synthesized through thermal decomposition of [Cu(NH3)4]2+ solution without any surfactants and catalysts at low temperature. The products are characterized by X-ray diffraction (XRD) and field-emission scanning electron microscopy (FESEM). The possible formation Nanoflake-based flower-like CuO nanostructures have been synthesized through thermal decomposition of [Cu(NH3)4]2+ solution without any surfactants and catalysts at low temperature. The products are characterized by X-ray diffraction (XRD) and field-emission scanning electron microscopy (FESEM). The possible formation process based on the aggregation-recrystallization mechanism is proposed. Finally, the obtained flowerlike CuO hierarchical nanostructures have been used as the photocatalyst in the experiments. It is found that the asprepared flower-like CuO hierarchical nanostructures exhibit superior photocatalytic property on photocatalytic decomposition of Rhodamine B due to their hierarchical structures..
Frontiers of Optoelectronics
- Publication Date: Jan. 01, 1900
- Vol. 5, Issue 4, 429 (2012)
RESEARCH ARTICLE
Resonantly pumped 1645 nm Q-switched Er:YAG laser with a ring cavity
Lingni ZHU, Chunqing GAO, Ran WANG, Mingwei GAO, Xin WANG, and Hans Joachim EICHLER
This paper report an 1645 nm Er:YAG laser resonantly pumped by an Er-fiber laser operating at 1532 nm. 1.78W continous wave (CW) output power with a slope efficiency of 52% was obtained using a long ring cavity and an 1 at.% doped Er:YAG crystal. In Q-switched mode, the obtained pulse energy was 1.6 mJ at a repetition This paper report an 1645 nm Er:YAG laser resonantly pumped by an Er-fiber laser operating at 1532 nm. 1.78W continous wave (CW) output power with a slope efficiency of 52% was obtained using a long ring cavity and an 1 at.% doped Er:YAG crystal. In Q-switched mode, the obtained pulse energy was 1.6 mJ at a repetition rate of 500 Hz; for 1 kHz repetition rate, 1.2 mJ output energy was obtained..
Frontiers of Optoelectronics
- Publication Date: Jan. 01, 1900
- Vol. 5, Issue 4, 400 (2012)
Simple solutions for photonic power-efficient ultra-wideband system assisted by electrical bandpass filter
Jianji DONG, Yuan YU, Bowen LUO, Dexiu HUANG, and Xinliang ZHANG
We propose and experimentally demonstrate two simple solutions for power-efficient ultra-wideband (UWB) radio frequency (RF) system assisted by an electrical bandpass filter (EBPF). In the first solution, any optical Gaussian pulse with enough bandwidth is transmitted over optical fiber link, and then converted to a poWe propose and experimentally demonstrate two simple solutions for power-efficient ultra-wideband (UWB) radio frequency (RF) system assisted by an electrical bandpass filter (EBPF). In the first solution, any optical Gaussian pulse with enough bandwidth is transmitted over optical fiber link, and then converted to a power-efficient UWB pulse by an EBPF with a passband of 3.1-10.6 GHz. The transmission and modulation of UWB signal is processed in optical domain, whereas the generation of UWB is processed in electrical domain. Both UWB modulations of on-off keying (OOK) and binary phase shift keying (BPSK) are experimentally demonstrated. In the second solution, the EBPF is used to convert any electrical waveform to a power-efficient UWB pulse. Then the electrical UWB pulse is converted to an optical UWB pulse with a Mach-Zehnder modulator (MZM), and then distributed over long haul fiber link. These two solutions embody the advantages of both low-loss longhaul transmission of optical fiber and mature electrical circuits. And the millimeter-wave UWB signal is also demonstrated..
Frontiers of Optoelectronics
- Publication Date: Jan. 01, 1900
- Vol. 5, Issue 4, 403 (2012)
Competition mechanism of multiple four-wave mixing in highly nonlinear fiber: spatial instability and satellite characteristics
Liang ZHAO, Junqiang SUN, Xinliang ZHANG, and Cong CHEN
Competition mechanism in multiple four-wave mixing (MFWM) processes is demonstrated theoretically. Provided considering only two waves injected into a highly nonlinear fiber (HNLF), there are three modes displaying comprehensive dynamic behaviors, such as fixed points, periodic motion, and chaotic motion. Especially, MCompetition mechanism in multiple four-wave mixing (MFWM) processes is demonstrated theoretically. Provided considering only two waves injected into a highly nonlinear fiber (HNLF), there are three modes displaying comprehensive dynamic behaviors, such as fixed points, periodic motion, and chaotic motion. Especially, Mode C ofMFWM is emphasized by analyzing its phase-space trajectory to demonstrate nonlinear wavewave interactions. The study shows that, when the phasespace trajectory approaches or gets through a saddle point, a dramatic power depletion for the injected wave can be realized, with the representative point moving chaotically, but when phase-space trajectories are distributed around a center point, the power for the injected wave is retained almost invariable, with the representative point moving periodically. Finally, the evolvement of satellite wave over an optical fiber is investigated by comparing it with the interference pattern in Young’s double-slit experiment..
Frontiers of Optoelectronics
- Publication Date: Jan. 01, 1900
- Vol. 5, Issue 4, 414 (2012)
Rayleigh backscattering noise in single-fiber loopback duplex WDM-PON architecture
Duan LIU, Songnian FU, Ming TANG, Ping SHUM, and Deming LIU
This paper investigated the impact of Rayleigh backscattering (RB) noise in the proposed wavelengthdivision-multiplexed (WDM) single-fiber loopback access network. RB noise’s impacts on the downstream and upstream service were discussed in details. It was found that the receiver sensitivity was less sensitive when the This paper investigated the impact of Rayleigh backscattering (RB) noise in the proposed wavelengthdivision-multiplexed (WDM) single-fiber loopback access network. RB noise’s impacts on the downstream and upstream service were discussed in details. It was found that the receiver sensitivity was less sensitive when the seeding-light power was below - 12.6 dBm. And for the uplink RB noise, a higher reflective semiconductor optical amplifier (RSOA)’s bias current results in lower receiver sensitivity..
Frontiers of Optoelectronics
- Publication Date: Jan. 01, 1900
- Vol. 5, Issue 4, 435 (2012)
Heterogeneous photocatalytic treatment of wastewater in ultraviolet light irradiation—photocatalyst Bi2WO6 microsphere with high repeatability
Xiaojing Lu, Yin PENG, and Zhengzheng HAN
The treatment of wastewater that includes toxic organic pollutants such as dyes, phenoaniline, phenols and their derivatives is still a challenge due to their biorecalcitrant and acute toxicity to the widespread acceptance of water recycling. Three-dimensional (3D) Bi2WO6 microsphere was synthesized by the hydrothermalThe treatment of wastewater that includes toxic organic pollutants such as dyes, phenoaniline, phenols and their derivatives is still a challenge due to their biorecalcitrant and acute toxicity to the widespread acceptance of water recycling. Three-dimensional (3D) Bi2WO6 microsphere was synthesized by the hydrothermal method using Bi(NO3)3 and Na2WO4 as raw materials. This structure exhibits high photocatalytic activity for the dyes, toxic organic compounds. The degradation of methlyene blue is 100% in 30 min, 4-nitrylphenol is 95% in 60 min and p-nitrylphenol is 95% in 75 min in ultraviolet (UV) light irradiation. 3D Bi2WO6 microsphere is also a good photocatalyst to treat the printing and dyeing sewage, and exhibits high repeatability. After being used the 20th time, Bi2WO6 still has high activity to degrade the printing and dyeing sewage, which is very important for a photocatalyst to be used in industry. This study will pave a new way to treat industry wastewater..
Frontiers of Optoelectronics
- Publication Date: Jan. 01, 1900
- Vol. 5, Issue 4, 439 (2012)
Homogeneous and inhomogeneous broadening effects on static and dynamic responses of quantum-dot semiconductor optical amplifiers
Hussein TALEB, and Kambiz ABEDI
In this paper, the effects of homogeneous and inhomogeneous broadenings on the response of quantumdot semiconductor optical amplifier (QD-SOAs) are investigated. For the first time, the state space model is used to simulate static and dynamic characteristics of the QD-SOA. It is found that with decreasing the homogeneoIn this paper, the effects of homogeneous and inhomogeneous broadenings on the response of quantumdot semiconductor optical amplifier (QD-SOAs) are investigated. For the first time, the state space model is used to simulate static and dynamic characteristics of the QD-SOA. It is found that with decreasing the homogeneous and inhomogeneous broadenings, the saturation power of the QD-SOA decreases and the optical gain and the ultrafast gain compression increase. Simulation results show that with decreasing the homogeneous broadening from 20 to 1 meV, the gain compression increases from 40% to 90%, the unsaturated optical gain becomes approximately tripled, and the saturation power becomes two times less. Also, simulations demonstrate that with decreasing the inhomogeneous broadening from 50 to 25 meV, the gain compression increases from less than 50% to more than 90%, the unsaturated optical gain becomes approximately 10-fold, and the saturation power becomes three times less. In addition, it is found that the homogeneous and inhomogeneous linewidths should be small for nonlinear applications. The homogeneous and inhomogeneous broadenings need to be large enough for linear applications..
Frontiers of Optoelectronics
- Publication Date: Jan. 01, 1900
- Vol. 5, Issue 4, 445 (2012)
Proposal for modeling of tapered quantum-dot semiconductor optical amplifiers
[in Chinese], and [in Chinese]
To compensate for the loss of carrier density along the active region of quantum-dot semiconductor optical amplifiers (QD-SOAs), tapered structure of the waveguide is introduced. In this paper, a method for theoretically modeling of such devices is proposed, and according to that model different shapes of tapered wavegTo compensate for the loss of carrier density along the active region of quantum-dot semiconductor optical amplifiers (QD-SOAs), tapered structure of the waveguide is introduced. In this paper, a method for theoretically modeling of such devices is proposed, and according to that model different shapes of tapered waveguides are studied. This study is pivoted around the optical gain and cross-gain modulation (XGM) of the QDSOA under investigation to show how altering the shape of the waveguide affects the main characteristics of the device. For doing so, the rate equation model has been employed and solved through finite difference method and MATLAB ODE. Through this, as long as monotonically increasing profiles for the width of the waveguide are used, the shape of the waveguide has a negligible effect on the gain which mainly depends on the width ratio of the waveguide output to its input. However, this carrier compensation has adverse effect on the XGM, where its efficiency rely on how the pump signal can effectively reduce carrier density and upset the gain..
Frontiers of Optoelectronics
- Publication Date: Jan. 01, 1900
- Vol. 5, Issue 4, 457 (2012)
RESERACH ARTICLE
Influence of facet reflection of SOA on SOA-integrated SGDBR laser
Tan SHU, Yonglin YU, Hui LV, Dexiu Huang, Kai SHI, and Liam BARRY
A combined model of the transmission-line laser model (TLLM) and the digital filter approach is developed to simulate the shuttering characteristic of a semiconductor optical amplifier (SOA), which is integrated with a sampled grating distributed Bragg reflector (SGDBR) laser, to create a so called SOA-SGDBR laser. TheA combined model of the transmission-line laser model (TLLM) and the digital filter approach is developed to simulate the shuttering characteristic of a semiconductor optical amplifier (SOA), which is integrated with a sampled grating distributed Bragg reflector (SGDBR) laser, to create a so called SOA-SGDBR laser. The SOA section acts as a shutter to blank the laser output during wavelength switching events. Simulated results show that the turn-on edge of the SOA blanking process will oscillate when the facet reflection of SOA is relatively high. This phenomenon is also observed by experiments..
Frontiers of Optoelectronics
- Publication Date: Jan. 01, 1900
- Vol. 5, Issue 4, 390 (2012)
An ellipse detection method for 3D head image fusion based on color-coded mark points
Zhen GUO, Xu LIU, Han WANG, and Zhenrong ZHENG
In this paper, we proposed a new kind of mark points coded by color and a new quasi-ellipse detector on pixel level. This method is especially applicable to threedimensional (3D) head panoramic reconstruction. Images of adjacent perspectives can be stitched by matching pasted color-coded mark points in overlap area to In this paper, we proposed a new kind of mark points coded by color and a new quasi-ellipse detector on pixel level. This method is especially applicable to threedimensional (3D) head panoramic reconstruction. Images of adjacent perspectives can be stitched by matching pasted color-coded mark points in overlap area to calculate the transformation matrix. This paper focuses on how the color-coded mark points work and how to detect and match corresponding points from different perspectives. Tests are performed to show the efficiency and accuracy of this method based on the original data obtained by structured light projection..
Frontiers of Optoelectronics
- Publication Date: Jan. 01, 1900
- Vol. 5, Issue 4, 395 (2012)
REVIEW ARTICLE
Optical fiber amplifiers for space-division multiplexing
Dagong JIA, Haiwei ZHANG, Zhe JI, Neng BAI, and Guifang LI
Recently, space-division multiplexing (SDM) techniques using multi-core fiber (MCF) and few-mode fiber (FMF) have been introduced into optical fiber communication to increase transmission capacity. Two main types of optical fiber amplifiers based on the Erbiumdoped fiber (EDF) and the Raman effect have been developed tRecently, space-division multiplexing (SDM) techniques using multi-core fiber (MCF) and few-mode fiber (FMF) have been introduced into optical fiber communication to increase transmission capacity. Two main types of optical fiber amplifiers based on the Erbiumdoped fiber (EDF) and the Raman effect have been developed to amplify signals in the MCF and FMF. In this paper, we reviewed the principles and configurations of these amplifiers..
Frontiers of Optoelectronics
- Publication Date: Jan. 01, 1900
- Vol. 5, Issue 4, 351 (2010)
Recent development in colloidal quantum dots photovoltaics
Li PENG, Jiang TANG, and Mingqiang ZHU
The increasing demand for sustainable and green energy supply spurred the surging research on highefficiency, low-cost photovoltaics. Colloidal quantum dot solar cell (CQDSC) is a new type of photovoltaic device using lead chalcogenide quantum dot film as absorber materials. It not only has a potential to break the 33%The increasing demand for sustainable and green energy supply spurred the surging research on highefficiency, low-cost photovoltaics. Colloidal quantum dot solar cell (CQDSC) is a new type of photovoltaic device using lead chalcogenide quantum dot film as absorber materials. It not only has a potential to break the 33% Shockley-Queisser efficiency limit for single junction solar cell, but also possesses low-temperature, high-throughput solution processing. Since its first report in 2005, CQDSCs experienced rapid progress achieving a certified 7% efficiency in 2012, an averaged 1% efficiency gain per year. In this paper, we reviewed the research progress reported in the last two years. We started with background introduction and motivation for CQDSC research.We then briefly introduced the evolution history of CQDSC development as well as multiple exciton generation effect. We further focused on the latest efforts in improving the light absorption and carrier collection efficiency, including the bulk-heterojunction structure, quantum funnel concept, band alignment optimization and quantum dot passivation. Afterwards, we discussed the tandem solar cell and device stability, and concluded this article with a perspective. Hopefully, this review paper covers the major achievement in this field in year 2011-2012 and provides readers with a concise and clear understanding of recent CQDSC development..
Frontiers of Optoelectronics
- Publication Date: Jan. 01, 1900
- Vol. 5, Issue 4, 358 (2012)
Recent progress on tandem structured dye-sensitized solar cells
Dehua XIONG, and Wei CHEN
Tandem structured dye-sensitized solar cells (DSSCs) can take full advantage of sunlight, effectively broadening the absorption spectrum of the cell, resulting in a higher open circuit voltage or short circuit current than that of the conventional DSSC with single light absorber. The theoretical maximum efficiency is tTandem structured dye-sensitized solar cells (DSSCs) can take full advantage of sunlight, effectively broadening the absorption spectrum of the cell, resulting in a higher open circuit voltage or short circuit current than that of the conventional DSSC with single light absorber. The theoretical maximum efficiency is therefore suggested to be over the Schottky-Queisser limit of 33%. Accordingly, tandem design of DSSC is thought to be a promising way to break the performance bottleneck of DSSC. Besides, the tandem designs also broaden the application diversity of DSSC technology, which will accelerate its scale-up industrial application. In this paper, we have reviewed the recent progress on photo-electrochemical applications associated with kinds of tandem designs of DSSCs, in general, which are divided into three kinds: “ntype DSSC + n-type DSSC,” “n-type DSSC + p-type DSSC” and “n-type DSSC + other solar conversion devices.” The working principles, advantages and challenges of these tandem structured DSSCs have been discussed. Some possible solutions for further studies have been also pointed out together..
Frontiers of Optoelectronics
- Publication Date: Jan. 01, 1900
- Vol. 5, Issue 4, 371 (2012)
© Copyright 2018-2021 | Chinese Laser Press. All Rights Reserved 沪ICP备15018463号-20