Intrapulse Frequency Sweeping in CO2 TEA Lasers

Author:

Willetts D V,Harris M R

Abstract

Frequency chirps within the output pulse of CO2 lasers limit their usefulness in coherent detection systems. We present an in-depth study of the mechanisms responsible for the intrapulse chirp, so that it may be controlled by suitable laser design. Since on the timescale of a few μs the resonator is mechanically rigid (see below), these frequency variations must arise from refractive index changes within the cavity. Such changes may arise from laser action1 as well as from discharge induced effects2,3; to avoid confusion the processes associated with the discharge are described first by observing refractive index changes in CO2-free discharges which cannot lase under our experimental conditions. The method used was to insert the TEA discharge within the resonator of a cw CO2 laser whose operating frequency was monitored by heterodyning with a cw CO2 local oscillator. The index changes arising within the discharge thus give rise to frequency changes exactly as would result from the same phenomena in a TEA laser. The beat signal is recorded and the temporal variation of beat frequency extracted from the positions of the zero crossings.

Publisher

Optica Publishing Group

同舟云学术

1.学者识别学者识别

2.学术分析学术分析

3.人才评估人才评估

"同舟云学术"是以全球学者为主线,采集、加工和组织学术论文而形成的新型学术文献查询和分析系统,可以对全球学者进行文献检索和人才价值评估。用户可以通过关注某些学科领域的顶尖人物而持续追踪该领域的学科进展和研究前沿。经过近期的数据扩容,当前同舟云学术共收录了国内外主流学术期刊6万余种,收集的期刊论文及会议论文总量共计约1.5亿篇,并以每天添加12000余篇中外论文的速度递增。我们也可以为用户提供个性化、定制化的学者数据。欢迎来电咨询!咨询电话:010-8811{复制后删除}0370

www.globalauthorid.com

TOP

Copyright © 2019-2024 北京同舟云网络信息技术有限公司
京公网安备11010802033243号  京ICP备18003416号-3