December 2009

Headline News Innovation and Development

Applied Technology

Basic Science Cooperation between CAS and Local Authorities
Bioscience International Cooperation Brief News Geoscience  
Innovation and Development

New Step of Amplifier System

The Applied Optics of the Optical Society of America published at its vol.48 issue 29 a thesis entitled ¡°Single-frequency linearly polarized master-oscillator fiber power amplifier system and its application in high fill factor coherent beam combining¡± jointly written by Qi Yunfeng, Liu Chi, Zhou Jun, Lou Qihong and Chen Weibiao from the Advanced Laser Technique and Application System Laboratory, Shanghai Institute of Optics and Fine Mechanics and pictures of this research result on its front cover in October 2009. This article reported in detail the characteristics of power, spectrum and phase noise of the high-efficiency single-frequency linearly polarized master-oscillator fiber power amplifier system based on MOPFA technology and the near diffraction-limited single-mode laser output obtained through mode control technology. The single-frequency fiber amplifier system developed by the Shanghai Institute of Optics and Fine Mechanics has been successfully used in high-power laser coherent beam combining technology and obtained ideal coherent effect.

CPT Atomic Frequency Standard Prototype

Recently, a research group headed by Prof. Gu Sihong of the Wuhan Institute of Physics and Mathematics, CAS, after three years¡¯ hard work, successfully developed the fourth version CPT atomic frequency standard prototype, which is in parallel with the advanced international level. The passive coherent population trapping (CPT) atomic frequency standard (¡°CPT frequency standard¡±) is a new type of atomic standard realized by using CPT phenomenon. In 2006, the Wuhan Institute of Physics and Mathematics, CAS developed its¡¯ first CPT frequency standard prototype in China. Through continuous improvement, the fourth-generation prototype newly developed has much smaller size but greatly improved indexes. The size of this prototype is 165 ml and its power consumption is 2.7W. Compared with the lamp-pumped rubidium frequency standard that is most commonly used currently, it has smaller size and lower power consumption. As a new-generation of small-sized atomic frequency standard, it has a good prospect for application in remote communication system timing and large-scale communication network synchronization.

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