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Chinese Optics Letters 第3卷 第12期

Author Affiliations
Abstract
1 College of Physics & Electronic Engineering, Xinyang Normal University, Xinyang 464000
2 College of Physics & Information Engineering, Henan Normal University, Xinyang 453007
3 Institute of Atomic and Morlecular Physics, Sichuan University, Chengdu 610065
The accurate dissociation energy and equilibrium geometry of the b3Π state of 7LiH molecule is calculated using a symmetry-adapted-cluster configuration-interaction method in full active space. And the calculated results are 0.2580 eV and 0.1958 nm for the dissociation energy and equilibrium geometry, respectively. The whole potential energy curve for the b3Π state is also calculated over the internuclear separation range from about 0.10 to 0.54 nm. The results are fitted by the Murrell-Sorbie function. It is found that the Murrell-Sorbie function form, which is mainly used to fit the ground-state potential energy function, is well suitable for the excited triplet b3Π state. The vertical excitation energy from the ground state to the b3Π state is calculated to be 4.233 eV. Based on the analytic potential energy function, the harmonic frequency of 610.88 cm^(-1) about this state is firstly estimated. Compared with other theoretical results, this work is the most complete effort to deal with the analytic potential energy function and the harmonic frequency of this state.
020.2070 effects of collisions 020.7010 trapping 
Chinese Optics Letters
2005, 3(12): 12683
Author Affiliations
Abstract
1 Shanghai Institute of Technical Physics, Chinese Academy of Sciences, Shanghai 200083
2 Graduate School of the Chinese Academy of Sciences, Beijing 100039
An airborne pushbroom hyperspectral imager (APHI) with wide field (42 deg. field of view) is presented. It is composed of two 22 deg. field of view (FOV) imagers and can provide 1304 pixels in spatial dimension, 124 bands in spectral dimension in one frame. APHI has a bandwidth ranging from 400 to 900 nm. The spectral resolution is 5 nm and the spatial resolution is 0.6 m at 1000-m height. The implementation of this system is helpful to overcome the restriction of FOV in pushbroom hyperspectral imaging in a more feasible way. The electronic and optical designs are also introduced in detail.
300.6320 spectroscopy high-resolution 110.0110 imaging systems 220.4830 optical systems design 
Chinese Optics Letters
2005, 3(12): 12689
Author Affiliations
Abstract
1 College of Laser Engineering, Beijing University of Technology, Beijing 100022
2 College of Physics Science and Information Engineering, Liaocheng University, Liaocheng 252059
3 Yonggang Wang
4 Institute of Semiconductors, Chinese Academy of Sciences, Beijing 100083
A flash-lamp-pumped Nd:YAG regenerative amplifier has been developed at 1.06 μm, seeded with 10-ps pulses from a diode-end-pumped and mode-locked Nd:YAG oscillator with homemade semiconductor saturable absorber mirror (SESAM). The pulse energy was amplified to 2 mJ by the regenerative amplifier at 10-Hz repetition rate. In two-stages amplifier the regenerative amplified pulse energy was amplified to 100 mJ, and 35-mJ double frequency at 532 nm was obtained by extra-cavity double frequency with a KTP crystal.
140.3280 laser amplifiers 140.4050 mode-locked lasers 140.3580 lasers solid-state 
Chinese Optics Letters
2005, 3(12): 12692
Author Affiliations
Abstract
State Key Laboratory of Precision Measurement Technology and Instruments, Department of Precision Instruments, Tsinghua University, Beijing 100084
The modes competition characteristics in birefringence cavity laser are studied in different regions of the gain curve. The mode's intensity modulation depth with modes competition is much deeper than that without modes competition. When the average intensities of the two modes are comparable, the intensity modulation depth of either mode reaches its maximum. Modes competition can do more contribution to the mode's modulation depth than the percentage of light reflected back into the laser cavity does. These characteristics can be used to improve the sensitivity of an optical feedback system. A modes competition factor is introduced to either mode's intensity expression which describes the laser intensity more precisely.
140.0140 lasers and laser optics 120.3180 interferometry 260.1440 birefringence 260.3160 interference 
Chinese Optics Letters
2005, 3(12): 12694
Author Affiliations
Abstract
1 Institute of Applied Laser, Kunming University of Science and Technology, Kunming 650093
2 CETHIL UMR 5008 INSA de Lyon Batiment S. Carnot 20, Avenue Albert Einstein 69621 Villeurbanne Cedex, France
Based on segmentation-recombination principle, a specific optical device is designed to homogenize a high-power CO2 laser beam which is used as a heating source. A model is developed to simulate the intensity distribution of converted laser beam. The results show that the theoretical simulation is consistent with experimental record. The uniformity of converted beam spot is discussed. After modifying the optical parameters of current device, a new optical system is given, through which the uniformity of shaped beam spot is improved remarkably.
140.3300 laser beam shaping 140.3470 lasers carbon dioxide 220.0220 optical design and fabrication 230.0230 optical devices 
Chinese Optics Letters
2005, 3(12): 12698
Author Affiliations
Abstract
Shanghai Institute of Optics and Fine Mechanics, Chinese Academy of Sciences, Shanghai 201800
The optical loss coefficient at 1053-nm wavelength, influenced by Fe ions in N31-type Nd-doped phosphate laser glass, was determined precisely and analyzed in detail. It is found that the optical loss coefficient per unit of Fe concentration (cm^(-1)/ppmw) increases with Fe concentration in the range of 0---300 ppmw, but it approaches a constant as the Fe concentration is larger than 300 ppmw. Such a concentration effect is due to a shift in the redox equilibrium between Fe3+ and Fe2+ ions in the glass. The effect of oxygen pressure, temperature, and variable valence states of other metal ions in glass samples on the optical loss is also discussed.
160.2750 glass and other amorphous materials 160.6990 transition metal-doped materials 300.1030 absorption 140.3530 lasers neodymium 
Chinese Optics Letters
2005, 3(12): 12701
Author Affiliations
Abstract
Key Laboratory of Optical and Magnetic Resonance Spectroscopy (East China Normal University), Ministry of Education, Department of Physics, and Department of Chemistry, East China Normal University, Shanghai 200062
Micro-Raman spectroscopy is employed to identify the normal and malignant human stomach cells. For the cancer cell, the reduced intensity of the Raman peak at 1250 cm^(-1) indicates that the protein secondary structure transforms from β-sheet or disordered structures to α-helical, while the increased intensity of the symmetric PO2 stretching vibration mode at 1094 cm^(-1) shows the increased DNA content. The ratio of the intensity at 1315 cm^(-1) to that at 1340 cm^(-1) reduces from 1.8 for the normal cell to 1.1 for the cancer cell in the course of canceration, and the ratio of the intensity at 1655 cm^(-1) to that at 1450 cm^(-1) increases from 1.00 for the cancer cell to 1.26 for the normal cell which indicates that the canceration of stomach cell may induce saturation of the lipid chain.
300.6450 spectroscopy Raman 170.5660 Raman spectroscopy 170.0170 medical optics and biotechnology 170.1530 cell analysis 
Chinese Optics Letters
2005, 3(12): 12705
Author Affiliations
Abstract
Department of Physics, State Key Laboratory on Fiber-Optic Local Area Communication Networks and Advanced Optical Communication Systems, Shanghai Jiao Tong University, Shanghai 200240
A method for generating multi-wavelength light source is theoretically investigated by optical parametric oscillation (OPO) in aperiodic optical superlattice (AOS). The effects of domain errors caused by the room-temperature electric poling process are checked. The relationship between the linewidth and the block length is also discussed.
190.4970 parametric oscillators and amplifiers 190.2620 frequency conversion 160.4330 nonlinear optical materials 
Chinese Optics Letters
2005, 3(12): 12708
Author Affiliations
Abstract
1 College of Precision Instrument and Optoelectronics Engineering, Key Laboratory of Optoelectronics Information Technical Science, EMC, Tianjin University, Tianjin 300072
2 Department of Physics, Hong Kong University of Science and Technology, Hong Kong
A method for fabricating three-dimensional (3D) photonic crystals (PhCs) easily and simply, by using a visible light (~532 nm) to pass one triangular pyramid to form non-coplanar multi-beam interference, named laser interference etching technique, is reported. In the experiment, we exposed a 9-μm-thick photo-resist on the silicon substrate with exposure intensities of 150, 180, and 220 mJ/cm2, and produced the periodical nanostructures. Through varying a common angle in the triangular pyramid, other interference patterns can be obtained to fabricate various PhCs.
220.3740 lithography 220.4000 microstructure fabrication 260.3160 interference 
Chinese Optics Letters
2005, 3(12): 12712
Author Affiliations
Abstract
1 Department of Electronic Science and Technology, Huazhong University of Science and Technology, Wuhan 430074
2 Department of Physics, Hubei Normal University, Huangshi 435002
The stability of three coupled Bose-Einstein condensate (BEC) solitons is investigated by the variational approach in two conventional time-independent trapping potentials. The effects of parameters of the potentials and the initial conditions of the BEC soliton system on the stationary state and self-trapping are discussed. It is found that the trapping potentials play an important role in the stability of the system and change the characteristics of the system, and there are different critical potential amplitude values corresponding to different trapping potentials and initial conditions of the BEC soliton system.
270.5530 pulse propagation and solitons 190.4720 optical nonlinearities of condensed matter 020.7010 trapping 
Chinese Optics Letters
2005, 3(12): 12715
Yi Li 1,2,3,*Xinjian Yi 2,3Tianxu Zhang 1,3
Author Affiliations
Abstract
1 Department of Control Science and Engineering, Huazhong University of Science and Technology, Wuhan 430074
2 Department of Optoelectronic Engineering, Huazhong University of Science and Technology, Wuhan 430074
3 Institute for Pattern Recognition and Artificial Intelligence, Huazhong University of Science and Technology, Wuhan 430074
A novel nanopolycrystalline structure of vanadium dioxide thin films is deposited on silicon or fused silica substrates by reactive ion sputtering and followed by an annealing. The characteristic analysis shows that the films have a columnar nanostructure with an average grain of 8 nm. The resistivities as a function of ambient temperatures tested by four-point probes for as-deposited films present that the transition temperature for nanostructure of vanadium dioxide films is near 35 Celsius degree which lowers about 33 Celsius degree in comparison with the transition temperature at 68 Celsius degree in its microstructure.
310.0310 thin films 160.6840 thermo-optical materials 160.1890 detector materials 350.5030 phase 
Chinese Optics Letters
2005, 3(12): 12719
Author Affiliations
Abstract
1 Institute of Laser Research, Qufu Normal University, Qufu 273165
2 Department of Physics, Qufu Normal University, Qufu 273165
Cu-Al2O3 (Ag-Al2O3) nano-array composite structures were obtained by alternating current (AC) electrodeposition Cu (Ag) into the pores of anodic alumina. Their transmitted spectra and polarized properties were investigated in detail. Experimental results indicate that the transmittance of Cu-Al2O3 is superior to that of Ag-Al2O3 in visible and infrared wavebands, and the extinction ratio is better than that of Ag-Al2O3 in near infrared waveband.
310.6860 thin films optical properties 160.4760 optical properties 260.3060 infrared 260.5430 polarization 
Chinese Optics Letters
2005, 3(12): 12722
Author Affiliations
Abstract
State Key Laboratory of Modern Optical Instrumentation, Zhejiang University, Hangzhou 310027
A novel method for spectral characterization of scanner was proposed in this paper, which combined the principal component analysis (PCA) and back propagation (BP) artificial neural network (ANN). The natural color system (NCS) color patches were adopted as the color targets. The accuracy of this method was evaluated by spectral root mean square (SRMS) error and the CIEDE2000 color difference specification. The experimental results showed that six principal components were appropriate and the spectral characterization accuracy was outstanding when a 3-20-6 BP net structure was used to estimate the scalars from the scanner red/green/blue (RGB) signals.
330.0330 vision and color 330.1690 color 330.1730 colorimetry 300.6550 spectroscopy visible 
Chinese Optics Letters
2005, 3(12): 12725
Author Affiliations
Abstract
1 Photon Craft Project, Shanghai Institute of Optics and Fine Mechanics, Chinese Academy of Sciences, Shanghai 201800
2 National Laboratory on High Power Laser and Physics, Shanghai Institute of Optics and Fine Mechanics, Chinese Academy of Sciences, Shanghai 201800
Microstructure optical fiber with uniform intensity distribution of the fundamental mode is proposed. The design guide line and characteristics of this kind fiber are demonstrated. The relationship between refractive index profile and structure parameters is investigated. The mechanism of forming uniform fundamental mode in these fibers is analyzed.
060.2430 fibers single-mode 140.3300 laser beam shaping 
Chinese Optics Letters
2005, 3(12): 686