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由种子Kerr不稳定的光放大
G Vampa1,2, T J Hammond3, M Nesrallah3
1Department of Physics, University of Ottawa, Ottawa, ON K1N 6N5, Canada. gvampa@stanford.edu thomas.brabec@uottawa.ca.
Science (New York, N.Y.)
|February 14, 2018
在PubMed 上查看摘要
概括
研究人员使用晶体中的调制不稳定性实现了超短激光脉冲的高增益放大. 这种方法提供了更广泛的调整性,避免了传统激光放大技术的局限性.
科学领域:
- 光学和光学
- 激光物理
- 材料科学
背景情况:
- 传统的秒激光放大方法依赖于激光介质或非线性晶体,由于化学性质或动量保存而对脉冲频率和带宽施加限制.
- 现有的技术往往限制了放大激光的可实现调整性和脉冲特性.
研究的目的:
- 展示一种超短激光脉冲高增强的新方法.
- 克服传统放大技术在调制性和带宽方面的局限性.
- 为了实现高强度,可广泛调节和超短放大激光脉冲.
主要方法:
- 在伊石 (Y3Al5O12) 晶体中播种调制不稳定.
- 使用五秒近红外脉冲作为源.
- 实现激光脉冲的放大,持续时间小于60毫秒.
主要成果:
- 证明了高增益放大 (大于1000).
- 实现了从0.5到2.2微米的扩大脉冲的广泛调制性.
- 每平方厘米高达1太瓦的强度.
- 成功放大了持续时间小于60 femtosecond的脉冲.
结论:
- 证明的方法绕过了兴奋剂和相匹配的限制,使其能够在更广泛的材料中放大,包括玻璃和晶体.
- 这种技术适用于产生超短,可调节的激光脉冲,甚至在远红外频率和单周期脉冲.
- 放大脉冲非常适合在固体和气体中研究强场过程.


