Journals >Chinese Optics Letters
Contents
2003
Volume: 1 Issue 7
20 Article(s)
Export citation format
Fiber Optics and Optical Communications
A self-seeded fiber laser incorporated with a fiber Bragg grating external cavity semiconductor laser
Jiangzhen Xia, Ronghui Qu, Haiwen Cai, Gaoting Chen, and Zujie Fang
A self-seeded fiber laser incorporated with a fiber Bragg grating external cavity semiconductor laser (FBGECL) and a Mach-Zehnder interferometer (MZI) were reported in this paper. The MZI provided a Q-switching with response time in the order of micro-seconds. The FBG-ECL provided narrow pulses as seeds to shorten the A self-seeded fiber laser incorporated with a fiber Bragg grating external cavity semiconductor laser (FBGECL) and a Mach-Zehnder interferometer (MZI) were reported in this paper. The MZI provided a Q-switching with response time in the order of micro-seconds. The FBG-ECL provided narrow pulses as seeds to shorten the Q-switched pulses. Experimentally, pulse width of 0.8 μs was measured, which was one fifth of the pulse width without self-seeding..
Chinese Optics Letters
- Publication Date: Jan. 01, 1900
- Vol. 1, Issue 7, 07380 (2003)
A novel chromatic dispersion monitoring method in terms of SOA spectral shift
Ying Shi, Minghua Chen, and Shizhong Xie
In this paper a novel low power online chromatic dispersion (CD) monitoring method is presented, which employs spectral shift in the semiconductor optical amplifier (SOA). The advantage of this method lies in that the required input power can be much reduced, and the filter output can be used in the dynamic CD compensaIn this paper a novel low power online chromatic dispersion (CD) monitoring method is presented, which employs spectral shift in the semiconductor optical amplifier (SOA). The advantage of this method lies in that the required input power can be much reduced, and the filter output can be used in the dynamic CD compensation system. The simulation indicates that the filtered power decreases with CD increases, and that the monitoring range increases as the filter bandwidth increases..
Chinese Optics Letters
- Publication Date: Jan. 01, 1900
- Vol. 1, Issue 7, 07383 (2003)
Optimization of holey fiber for dispersion compensation
Yi Ni, Lei Zhang, and Jiangde Peng
Hermite-Gaussian functions were used to calculate the dispersion of holey fibers, when pitch was more than 0.6 μm, there was dispersion inflexion at 1.55 μm (wavelength), and the relation of the dispersion inflexion versus fiber structure was given. Calculations show that the dispersion of holey fiber could reach - 230Hermite-Gaussian functions were used to calculate the dispersion of holey fibers, when pitch was more than 0.6 μm, there was dispersion inflexion at 1.55 μm (wavelength), and the relation of the dispersion inflexion versus fiber structure was given. Calculations show that the dispersion of holey fiber could reach - 2300 ps/(nm·km), or they could compensate (to within ±4%) the dispersion of 120 times of their length of standard single mode fiber over a 100-nm range..
Chinese Optics Letters
- Publication Date: Jan. 01, 1900
- Vol. 1, Issue 7, 07385 (2003)
A novel multipriority reservation protocol for plastic optical fiber access network
Ning Zhang, and Rongjin Yu
In this paper, a novel multipriority reservation protocol for plastic optical fiber access network based on optical code division multiplexing access (OCDMA) technology is proposed. Conventional OCDMA system only allows finite units to transmit and access simultaneously according to the number of channels. The protocolIn this paper, a novel multipriority reservation protocol for plastic optical fiber access network based on optical code division multiplexing access (OCDMA) technology is proposed. Conventional OCDMA system only allows finite units to transmit and access simultaneously according to the number of channels. The protocol is proposed to resolve this problem. By using the reservation scheme and a distributed arbitration algorithm, channel collision and destination conflict can be avoided. The protocol can efficiently support the transmission of multimedia messages that require the different time-delays. At the same time, each optical network unit is equipped with a fixed optical encoder/decoder that is always tuned to channel forcontrol and the tunable optical encoder/decoder that is tuned to any of channel for data. The network throughput and average delay have been investigated by numerical analysis and simulation experiments. It is shown that the multipriority reservation protocol in this POF access network based on OCDMA technology is valid and efficient..
Chinese Optics Letters
- Publication Date: Jan. 01, 1900
- Vol. 1, Issue 7, 07388 (2003)
A novel differentiated services supporting scheme for optical burst switched networks
Jianxin Wang, Qingji Zeng, Zhizhong Zhang, and Hao Chi
In this letter, we analyze the drawback of tail-dropping contention resolution in optical burst switched networks. Once contention occurs, we adopt modified head-dropping policy to resolve contention. This policy drops the head of the contending burst only if the overlapping region of the two bursts is less than the whIn this letter, we analyze the drawback of tail-dropping contention resolution in optical burst switched networks. Once contention occurs, we adopt modified head-dropping policy to resolve contention. This policy drops the head of the contending burst only if the overlapping region of the two bursts is less than the whole contending burst size, otherwise drops the whole contending burst. In order to have a better support of differentiated service, a new burst assembly policy, namely, Priority-based proportional mixed burst assembly, is proposed. Simulation results show that the proposed scheme performs very well in terms of performance metrics such as the times of contention and packet loss probability..
Chinese Optics Letters
- Publication Date: Jan. 01, 1900
- Vol. 1, Issue 7, 07392 (2003)
Integrated Optics
Bend effect of the electrode for travelling wave integrated electro-optic modulators
Fuwen Zhang, Fushen Chen, and Kun Qiu
In this paper, we have studied electrode bend effects on electrical characteristics of the modulator in the three aspects, which are arc length, characteristic impedance, and loss, applying the model in Ref. [1] and the finite element method (FEM). The results have shown that the effect only caused by the characteristiIn this paper, we have studied electrode bend effects on electrical characteristics of the modulator in the three aspects, which are arc length, characteristic impedance, and loss, applying the model in Ref. [1] and the finite element method (FEM). The results have shown that the effect only caused by the characteristic impedance is necessarily considered while its deviation is large, but others are negligible as we design a practical device. Finally, some transmission characteristics of coplanar line with different arc length of the bend have been tested, and the measured results are in good agreement with the theoretical analyses..
Chinese Optics Letters
- Publication Date: Jan. 01, 1900
- Vol. 1, Issue 7, 07401 (2003)
Fabrication of glass optical power splitter in thallium source by ion-exchange method
Zigang Zhou, and Desen Liu
The use of a new thallium-ion (Tl^(+)) source for glass optical power splitter fabrication based on a NaNO~~(3^(-)) Tl~~(2)SO~~(4) mixture is proposed and demonstrated. Planar optical power splitters were made using glassessuch as K~~(6), K~~(8), K~~(9). The optical quality of the devices prepared compares favorably wiThe use of a new thallium-ion (Tl^(+)) source for glass optical power splitter fabrication based on a NaNO_(3^(-)) Tl_(2)SO_(4) mixture is proposed and demonstrated. Planar optical power splitters were made using glassessuch as K_(6), K_(8), K_(9). The optical quality of the devices prepared compares favorably with the qualityobtained using other fabrication techniques (such as dry etching) and the processing time is considerablyreduced..
Chinese Optics Letters
- Publication Date: Jan. 01, 1900
- Vol. 1, Issue 7, 07404 (2003)
Lasers and Laser Optics
Sub-nanosecond strong pulse generated by backward Raman scattering
Zhenhuan Ye, Qihong Lou, Jingxing Dong, Yunrong Wei, and Lei Ling
Hundreds picosecond strong short-wavelength pulses have been generated by a backward Raman oscillator amplifier pumped with a 10-J KrF laser from Heaven-1 MOPA system. Not only high power but also high energy laser pulses have been obtained with an energy conversion efficiency up to 17%. 640-picosecond pulse duration wHundreds picosecond strong short-wavelength pulses have been generated by a backward Raman oscillator amplifier pumped with a 10-J KrF laser from Heaven-1 MOPA system. Not only high power but also high energy laser pulses have been obtained with an energy conversion efficiency up to 17%. 640-picosecond pulse duration was observed in our experiments by a 1.5-GHz-bandwidth oscilloscope corresponding to 34 times of pulse compression rate..
Chinese Optics Letters
- Publication Date: Jan. 01, 1900
- Vol. 1, Issue 7, 07406 (2003)
Study on the optimum parameters for laser-solid interaction
Liyun Lin, Shengbo Wang, Dahao Guo, Hongxing Wu... and Yusheng Dai|Show fewer author(s)
The optimum parameters for laser propulsion are discussed, such as laser induced pressure on targets, interaction parameters (C~~(m), I~~(sp)) and optimum laser intensity I~~(s), etc. It is verified that the larger laser power density will induce higher thrusting force. It is also found that, to drive a 1.010-kg targetThe optimum parameters for laser propulsion are discussed, such as laser induced pressure on targets, interaction parameters (C_(m), I_(sp)) and optimum laser intensity I_(s), etc. It is verified that the larger laser power density will induce higher thrusting force. It is also found that, to drive a 1.010-kg target during confined laser ablation in vacuum and a 17.45-g one during direct laser ablation in air at the standard pressure, the needed minimum power intensities are on the same order of magnitude..
Chinese Optics Letters
- Publication Date: Jan. 01, 1900
- Vol. 1, Issue 7, 07408 (2003)
Derivation of the modification heating conduction equation of a kind of laser thermal effect by quantum mechanics
Lingyun Zhou, Canbang Zhang, Yiying Zhou, and Guangmin Wu
The Fourier equation of heat conduction predicts a paradox that the effect of a thermal impulse (e.g. the thermal effect in pulse laser) in an infinite medium; i.e., a thermal impulse is propagated in an infinite velocity. In order to solve the thermal transport paradox, C. W. Ulbrich and M. Chester have proposed the mThe Fourier equation of heat conduction predicts a paradox that the effect of a thermal impulse (e.g. the thermal effect in pulse laser) in an infinite medium; i.e., a thermal impulse is propagated in an infinite velocity. In order to solve the thermal transport paradox, C. W. Ulbrich and M. Chester have proposed the modification heat conduction equation respectively from different macroscopic viewpoint. This paper derived the modification heat conduction equation according to phonon model and quantum mechanics from microscopic viewpoint..
Chinese Optics Letters
- Publication Date: Jan. 01, 1900
- Vol. 1, Issue 7, 07411 (2003)
Nonlinear Optics
Orientation of azobenzene molecules in polymer films induced by all-optical poling
Xiaoxia Zhong, Shouyu Luo, Xiuqin Yu, Qu Li... and Jie Yin|Show fewer author(s)
A model of the alignment of azobenzene molecules in polymer film induced by all-optical poling is proposed and verified by experiment. We found that when the writing beams of frequencies ω and 2ω are both linearly polarized with their polarization directions parallel to each other, azobenzene molecules tend to reorientA model of the alignment of azobenzene molecules in polymer film induced by all-optical poling is proposed and verified by experiment. We found that when the writing beams of frequencies ω and 2ω are both linearly polarized with their polarization directions parallel to each other, azobenzene molecules tend to reorient to the direction perpendicular to the writing beams polarization. At the end of the writing process, more molecules orient to the direction perpendicular to the writing beams polarization than those orient to the parallel direction. The alignment of molecules parallel or perpendicular to the polarization of the writing beams is characteristic of polarity or no polarity, respectively. The alignment of molecules along the polarization of writing beams results in the second order nonlinearity in the polymer film. According to the model, a new method to improve the optical poling efficiency is put forward..
Chinese Optics Letters
- Publication Date: Jan. 01, 1900
- Vol. 1, Issue 7, 07414 (2003)
Quantum Optics
Effect of phase fluctuation on Hopf bifurcation in a ladder type atomic system
Chengpu Liu, Shangqing Gong, Zhenxun Zheng, and Zhizhan Xu
Hopf bifurcation inducing lasing without inversion has been analyzed by taking into account the effect of phase fluctuation in the driving field based on a closed three level ladder-type atomic model. It is shown that due to the phase fluctuation of the driving field, the necessary threshold increases significantly. FuHopf bifurcation inducing lasing without inversion has been analyzed by taking into account the effect of phase fluctuation in the driving field based on a closed three level ladder-type atomic model. It is shown that due to the phase fluctuation of the driving field, the necessary threshold increases significantly. Furthermore the area domain to get lasing without inversion decreases as the driving field’s linewidth increases..
Chinese Optics Letters
- Publication Date: Jan. 01, 1900
- Vol. 1, Issue 7, 07423 (2003)
Measurement of the wavelength modulation indices with selective reflection spectroscopy
Liantuan Xiao, Jianming Zhao, Wangbao Yin, Yanting Zhao... and Suotang Jia|Show fewer author(s)
The wavelength modulation indices are measured based on harmonic amplitude ratio of 4f~~(amp)/6f~~(amp) (4f~~(amp) and 6f~~(amp) are the 4- and 6-th harmonic central peak amplitudes correspondingly) with the Doppler-free selective reflection modulation spectroscopy. The experiments for the 6S~~(1/2)(F = 4) → 6P~~(3/2)(The wavelength modulation indices are measured based on harmonic amplitude ratio of 4f_(amp)/6f_(amp) (4f_(amp) and 6f_(amp) are the 4- and 6-th harmonic central peak amplitudes correspondingly) with the Doppler-free selective reflection modulation spectroscopy. The experiments for the 6S_(1/2)(F = 4) → 6P_(3/2)(F' = 5) transition of cesium D_(2) line with 30-MHz linewidth were carried out. The 4f- and 6f-harmonic signals were detected with two digital lock-in amplifiers separately. The maximum error for modulation indices measurement was ±0.1 within the range of m from 3 to 6. The non-linear modulation behaviour of an external cavity diode laser induced by voltage tuning was studied with this method. The method for modulation indices measurement does not require a solid etalon as usual for measuring the wavelength modulation depth and the absorption linewidth correspondingly..
Chinese Optics Letters
- Publication Date: Jan. 01, 1900
- Vol. 1, Issue 7, 07426 (2003)
Atomic and Molecular Physics
Polarization spectra of Rb atoms and their application in laser frequency stabilization
Kaijun Jiang, Jin Wang, Xianhua Tu, Ming He, and Mingsheng Zhan
Polarization spectra of rubidium atoms were investigated with different uncrossed angles between the polarizer and the analyzer. The variation of the spectra was derived theoretically as a function of arbitrary angle, and measured experimentally for different angles. The spectral profile of D~~(2) line of rubidium was Polarization spectra of rubidium atoms were investigated with different uncrossed angles between the polarizer and the analyzer. The variation of the spectra was derived theoretically as a function of arbitrary angle, and measured experimentally for different angles. The spectral profile of D_(2) line of rubidium was further used to stabilize the frequency of a diode laser. It was demonstrated that the laser linewidth was reduced to 2 MHz..
Chinese Optics Letters
- Publication Date: Jan. 01, 1900
- Vol. 1, Issue 7, 07377 (2003)
Instrumentation, Measurement, and Metrology
Single-pulse CARS spectra in solid propellant combustion at atmosphere pressure
Zhiyun Hu, Jingru Liu, Zhenrong Zhang, Xiaowei Guan... and Xisheng Ye|Show fewer author(s)
The unstable-resonator spatially enhanced detection (USED) coherent anti-stokes Raman spectroscopy (CARS) measurements of temperature and N~~(2) concentration in the combustion of solid propellant at atmosphere pressure are reported. The USED CARS measurement system has a high spatial solution of ~ 0.1 mm in diameter aThe unstable-resonator spatially enhanced detection (USED) coherent anti-stokes Raman spectroscopy (CARS) measurements of temperature and N_(2) concentration in the combustion of solid propellant at atmosphere pressure are reported. The USED CARS measurement system has a high spatial solution of ~ 0.1 mm in diameter and 3 mm in length, and permits instantaneous measurement at 10-Hz rate. The single-pulse N_(2) Q-branch CARS spectra have been obtained from the propellant combustion. The temperatures and N_(2) concentrations of the propellant flame at different height have been achieved by fitting the experimental data to theoretical spectra. The results indicate that the temperature is up to ~ 2500 K with N_(2) concentration in a range from 10% to 26%..
Chinese Optics Letters
- Publication Date: Jan. 01, 1900
- Vol. 1, Issue 7, 07395 (2003)
Stray light suppression in BRDF measurement infrared optical system
Chao Qi, Chunling Yang, Wenjuan Li, and Jingmin Dai
A set of system based on personal computer for the bi-directional reflectance distribution function (BRDF) measurement was developed, whose laser wavelengths cover 0.6328, 1.34, 3.39, and 10.6 μm from visible to infrared. Stray light in BRDF measurement system was analyzed. It can be reduced and suppressed by the desigA set of system based on personal computer for the bi-directional reflectance distribution function (BRDF) measurement was developed, whose laser wavelengths cover 0.6328, 1.34, 3.39, and 10.6 μm from visible to infrared. Stray light in BRDF measurement system was analyzed. It can be reduced and suppressed by the design of the system light path in BRDF measurement system, the choice of the measuring scheme, the processing to the optoelectronic signal, and the radiation control of the optical components and mechanical equipments. So the minimum measurable value of BRDF is less than 10^(-5)/sr..
Chinese Optics Letters
- Publication Date: Jan. 01, 1900
- Vol. 1, Issue 7, 07398 (2003)
OPTICAL DATA STORAGE
Readout of super-resolution marks with Ti thin film
Jingsong Wei, Yang Wang, Wendong Xu, Zhenrong Sun... and Fuxi Gan|Show fewer author(s)
Using Ti as the super-resolution reflective film to replace the Al reflective layer in conventional read-only optical disk, the recording marks with a diameter of 380 nm and a depth of 50 nm are read out in a dynamic testing device whose laser wavelength is 632.8 nm and numerical aperture of the lens is 0.40. The optimUsing Ti as the super-resolution reflective film to replace the Al reflective layer in conventional read-only optical disk, the recording marks with a diameter of 380 nm and a depth of 50 nm are read out in a dynamic testing device whose laser wavelength is 632.8 nm and numerical aperture of the lens is 0.40. The optimum Ti thin film thickness is 18 nm and the corresponding signal-noise-ratio is 32 dB..
Chinese Optics Letters
- Publication Date: Jan. 01, 1900
- Vol. 1, Issue 7, 07420 (2003)
Ultrafast Optics
The study of nanojoule femtosecond laser ablation on organic glass
Xiaochang Ni, Ching-Yue Wang, Zhuan Wang, Minglie Hu... and Lu Chai|Show fewer author(s)
The Ti:sapphire oscillator is used to realize structural change in an organic glass (polymethyl -methacrylate (PMMA)). Single pulse fluence threshold of PMMA and the relation of the breakdown threshold with different numerical aperture objectives are determined using a formula deduced from an existent equation. Three-dThe Ti:sapphire oscillator is used to realize structural change in an organic glass (polymethyl -methacrylate (PMMA)). Single pulse fluence threshold of PMMA and the relation of the breakdown threshold with different numerical aperture objectives are determined using a formula deduced from an existent equation. Three-dimensional dots in the organic glass is performed at the same time..
Chinese Optics Letters
- Publication Date: Jan. 01, 1900
- Vol. 1, Issue 7, 07429 (2003)
The deformable mirror method of adaptive phase correction
Bin Tang, Yuxin Leng, Hanlin Peng, Zhengquan Zhang, and Lihuang Lin
In this paper, a simple method of phase correction by using a micromachined deformable mirror (MMDM) is demonstrated. With correction of high-order phases due to propagating through medium, we obtained a clean pulse shape, flattened spectral phase and decreased the femtosecond laser pulse duration. It is shown by our eIn this paper, a simple method of phase correction by using a micromachined deformable mirror (MMDM) is demonstrated. With correction of high-order phases due to propagating through medium, we obtained a clean pulse shape, flattened spectral phase and decreased the femtosecond laser pulse duration. It is shown by our experiment that the deformable mirror is an effective and easy method for adaptive phase correction..
Chinese Optics Letters
- Publication Date: Jan. 01, 1900
- Vol. 1, Issue 7, 07432 (2003)
Atmospheric and Oceanic Optics
Raman lidar measurements of tropospheric water vapor over Hefei
Yonghua Wu, Huanling Hu, Shunxing Hu, and Jun Zhou
L625 Raman lidar has been developed for water vapor measurements over Hefei, China since September 2000. By transmitting laser beam of frequency-tripled Nd:YAG laser, Raman scattering signals of water vapor and nitrogen molecules are simultaneously detected by the cooled photomultipliers with photon counting mode. WateL625 Raman lidar has been developed for water vapor measurements over Hefei, China since September 2000. By transmitting laser beam of frequency-tripled Nd:YAG laser, Raman scattering signals of water vapor and nitrogen molecules are simultaneously detected by the cooled photomultipliers with photon counting mode. Water vapor mixing ratios measured by Raman lidar show the good agreements with radiosonde observations, which indicates this Raman lidar is reliable. Many observation cases show that aerosol optical parameters have the good correlation with water vapor distribution in the lower troposphere..
Chinese Optics Letters
- Publication Date: Jan. 01, 1900
- Vol. 1, Issue 7, 07373 (2003)
© Copyright 2018-2021 | Chinese Laser Press. All Rights Reserved 沪ICP备15018463号-20