A simple and efficientdiode-pumped Nd : YAG master-oscillator power-amplifier (MOPA) system is introduced. Themaster oscillator provides a pulse energy of 1. 13 J at a repetition rate of 100 Hz. Themaximum pulse energy of the MOPA system is 2. 35 J, and the corresponding totaloptical-to-optical efficiency is 39 ％. The experimental results are well agreed to the theoreticalcalculation.Xinjiang Uygur Autonomous Region Province, in 1968. He received the B. S. degree fromXinjiang Normal University in 1992 and M. Sc. degree from the Hebei University in 2003. Heis presently pursuing the Ph. D at Institute of Physics,CAS, and his research focuses onhigh-power diode-pumped solid-state lasers.Tel:010-82648093 Email:xjyxd@126.com杨晓冬（中科院物理研究所,北京凝聚态物理国家实验室,北京,100080;嘉应学院,物理系,广东,梅州,514015）孙志培（中科院物理研究所,北京凝聚态物理国家实验室,北京,100080）毕勇（中科院物理研究所,北京凝聚态物理国家实验室,北京,100080）薄勇（中科院物理研究所,北京凝聚态物理国家实验室,北京,100080）耿爱丛（中科院物理研究所,北京凝聚态物理国家实验室,北京,100080）彭钦军（中科院物理研究所,北京凝聚态物理国家实验室,北京,100080）张恒利（中科院物理研究所,北京凝聚态物理国家实验室,北京,100080）崔大复（中科院物理研究所,北京凝聚态物理国家实验室,北京,100080）许祖彦（中科院物理研究所,北京凝聚态物理国家实验室,北京,100080）High Technology Research and Development Program of China (2002AA311120)

The pump fields requirements for athermal laser amplifier and oscillator are described.The expressions of the pump fields are derived by use of rate equations. The pump distribution of an ytterbium-doped KY(WO4 )2 crystal is analyzed as an athermal lasers. For athermal laser amplifier, the pump intensity along the axis must be varied according to the laser intensity. With the increase of laser intensity, the pump intensity should be adjusted lower. For athermal laser oscillators, the pump distribution in the cavity is almost determined by the reflectivities of the rear and output coupler mirrors and gain media length. The pump intensity becomes lower and more close to uniform as the output coupler reflectivity is increased.

作者简介：卓壮,Tel:0531-86184172 Email:z.zhuo@sduln.com.cn

A diode-pumped CW mode-locked Nd∶YVO4 laser with a repetition rate of 1 GHz was demonstrated. The laser was passively mode locked by a semiconductor saturable absorber mirror (SESAM). The QML operation was successfully suppressed by using an output coupler with very low transmission (0.8%) and a 2 W LD pump source introducing a small pump spot in the laser crystal. The lasing oscillation threshold was 35 mW and CW mode locking threshold was 0.8 W. The maximum average output power was 210 mW with 1.6 W pump power.彭继迎（中国科学院长春光学精密机械与物理研究所,长春,130033;中国科学院研究生院,北京,100039）檀慧明（中国科学院长春光学精密机械与物理研究所,长春,130033）王保山（中国科学院长春光学精密机械与物理研究所,长春,130033;中国科学院研究生院,北京,100039）苗杰光（中国科学院长春光学精密机械与物理研究所,长春,130033;中国科学院研究生院,北京,100039）钱龙生（中国科学院长春光学精密机械与物理研究所,长春,130033）王勇刚（中国科学院半导体研究所,北京,100083）马骁宇（中国科学院半导体研究所,北京,100083）

born in 1975, Henan Province. She graduated from Changchun Institute of Optics, FineMechanics & Physics, Chinese Academy of Sciences in 2005 and got her Doctorial degree.She majors in microcavity organic light emitting diode and polymer laser.She is interestedin the application of the organic/polymer light emitting diode to the display and lightingand published about 20 correlative papers.Tel:0371-67763701 Email:fengymgma@163.com

in 1968,and graduated from Sichuan Normal University in 1989. Now he is currently workingas a Ph. D. candidate at Institute of Laser Physics and Chemistry,Sichuan University. Hisresearch interest mainly includes the propagation and transformation of ultrashort pulsedbeams.Tel:028-85412819 Email:qihui_zou@163.com

作者简介：孔繁敏,Tel:0531-88361608 Email:kongfm@sdu.edu.cn

作者简介：牛憨笨,Tel:0755-26538579 Email:hbniu@szu.edu.cn

Based on the propagation law of partially coherent light, the spectral changes of Gaussian Schell-model (GSM) beams passing through an astigmatic aperture lens are studied. It is shown that as compared with the original spectrum of the source, the axial spectrum in the focused field shifts to lower or higher frequency, which is defined as a spectral shift. Thedependence of spectral shift of GSM beams on the astigmatism of the lens, spatial coherence of GSM beams and the aperture diffraction is investigated in detail. The numerical results show that these parameters affect the spectral shift noticeably. A comparison with the aberration-free case is made, and shows that the astigmatism affects the spectral behavior of GSM beams, the largerastigmatism results in larger spectral changes in general.

作者简介：徐军,Tel:021-56331687 Email:xujun@mail.shcne.ac.cn

作者简介：吕福云,Tel:022-23509856 Email:lufy@nankai.edu.cn

He'nan province on November, 1977. He graduated from Physics Department of Henan NormalUniversity in 1999 and he received his M. S. degree in Southwest China Normal Universityin 2005. His interest focus on optical fiber sensor andmicro-optics.Tel:027-67883423Email:lvtaohn@sma.com

作者简介：王丽,Tel:010-67392198 Email:lwang.1@bjut.edu.cn

作者简介：蒋刚毅,Tel:0574-87600935 Email:jianggangyi@126.com

作者简介：高协平,Tel:0732-8293249 Email:xpgao@xtu.edu.cn

作者简介：张新亮,Tel:027-87792242-803 Email:xlzhang@mail.hust.edu.cn

An ultra-broadband amplified spontaneous emission (ASE) source was proposed and demonstrated by using a combination of a novel 247 cm Bismuth-based Erbium-doped fiber and a conventional 10 m Erbium-doped fiber in a configuration of bi-directional pumps. The physical mechanism was explained and the performance was compared with those for some other similar configurations. Without any external spectral filters and with a total pump power of less than 240 mW,an ASE source with a wavelength range of 96 nm (1 522 nm～1 618 nm, over -20 dBm/2 nm)and a total output power of over 11 dBm was achieved by optimizing the EDFs' lengths and the pump powers. The -10 dB bandwidth and the peak power density of the output spectrum are over 87 nm and -2.5 dBm/2 nm, respectively.作者简介：CHEN Da-ru,Tel:0571-88206515-227 Email:daru@coer.zju.edu.cn

In a typical triangular arrangement of photonic crystal fiber (PCF), each air-hole is replaced by a pair of twin air-holes. Two neighboring air holes with the same spacing and fixed axes direction come into being twin air holes pairs and it is the basic cell in the cladding of PCF.In the central of section, not missing one air hole but missing a pair of twin air holes with higher refractive index material can localize optical field and become the core of PCF. All twin air holes are regularly arranged according to triangular arrangement in the cladding. In this novel PCF, an asymmetry character is aroused because of all twin air holes with identical axis direction, and birefringence relevant to axes direction of twin air holes is formed. Finite difference (FD) method is used to analyze modal character of PCF. The results of numerical calculation indicate that, the effective refractive index difference between two orthogonal directions Δneff can reach the magnitude of 10-4. Especially, the structure parameter of twin air holes can change birefringence in slight, such as increasing air hole size or reducing spacing of two air holes within every twin air holes all can increase birefringence effect.

作者简介：吴木生,Tel:0791-6958953 Email:sanmu70153@yahoo.com.cn