Relaxation of Dense Electron Plasma Induced by Femtosecond Laser in Dielectric Materials
Relaxation of Dense Electron Plasma Induced by Femtosecond Laser in Dielectric Materials
复制标题
飞秒激光在电介质材料中诱导的稠密电子等离子体的弛豫
DOI：
--
复制
发表时间：
2006
期刊：
影响因子：
--
通讯作者：
Gong Qi
中科院分区：
文献类型：
--
作者：
S. Quan;Jiang Hong;Liu Yi;Zhou Yong;Yang Hong;Gong Qi
利用泵浦-探测阴影成像技术研究了聚焦飞秒脉冲（130 fs，800 nm）在介质材料（钠钙玻璃、K9玻璃和SiO2晶体）中产生的电子等离子体。讨论了导带中电子等离子体的弛豫。在SiO2晶体中，观察到一个快速的自陷过程的捕获时间为150 fs，这是类似于在熔融石英。而在Soda Lime玻璃和K9玻璃中，没有发生自陷，并发现两个衰减过程：一个是传导电子在几皮秒内的能量弛豫过程，另一个是电子-空穴复合过程，时间尺度为100 ps。在所有这些材料中，导带中的电子碰撞时间τ也被测量为1 fs的量级。
Electron plasma induced by a focused femtosecond pulse (130 fs, 800 nm) in dielectric materials (Soda Lime glass, K9 glass, and SiO2 crystal) is investigated by pump-probe shadow imaging technology. The relaxation of the electron plasma in the conduction band is discussed. In SiO2 crystals, a fast self-trapping process with a trapping time of 150 fs is observed, which is similar to that in fused silica. However, in Soda Lime glass and K9 glass, no self-trapping occurs, and two decay processes are found: one is the energy relaxation process of conduction electrons within several picoseconds, another is an electron-hole recombination process with a timescale of 100 ps. The electron collision time τ in the conduction band is also measured to be in the order of 1 fs in all of these materials.