NYI: Studies of Ultrafast Processes Using High-Intensity and Short-Wavelength Light

最近，在超快激光器领域发生了一场革命。新的宽带固体激光材料，如掺钛蓝宝石，使得使用非常简单的激光器产生前所未有的短持续时间和高平均功率的脉冲成为可能。此外，最近开发的啁啾脉冲放大技术使得使用小型激光系统产生大于1太瓦的峰值功率成为可能。这些高功率脉冲，结合各种非线性光学技术，使第一次产生紫外和真空紫外波长的超短脉冲成为可能。我的计划是研究这些产生短波长的光的技术，然后使用持续时间为1-100秒的短波脉冲来研究材料和化学系统中的动态过程。由于原子、分子和固体中的高度激发态可以用短波长的光到达，它们的寿命通常很短，波长短、持续时间短的光源作为研究工具将特别有用。我感兴趣的过程包括高带隙材料中的载流子动力学和介电击穿动力学；分子动力学和有机分子的分子控制（有机分子通常在深紫外中吸收最强烈的光）；以及利用紫外光发射的表面动力学。

Recently, there has been a revolution in the field of ultrafast lasers. New broadband solid-state laser materials such as titanium- doped sapphire make it possible to produce pulses of unprecedented short duration and high average power, using very simple lasers. Also, the recently-developed technique of chirped-pulse amplification makes it possible to generate peak powers of greater than a terawatt using a small-scale laser system. These high-power pulses, in combination with various nonlinear- optical techniques, make it possible for the first time to generate ultrashort pulses at ultraviolet and vacuum-ultraviolet wavelengths. My plan is to study these techniques of generating short-wavelength light, and then to use short-wavelength pulses of 1-100 fs duration to study dynamic processes in material and chemical systems. Since the highly- excited states in atoms, molecules, and solids that are accessible with short-wavelength light typically have very short lifetimes, a source with short wavelength and short time duration will be particularly useful as a research tool. Processes of interest to me include carrier dynamics in high-bandgap materials and dielectric breakdown dynamics; molecular dynamics and molecular control of organic molecules (which typically absorb light most strongly in the deep-UV); and surface dynamics using ultraviolet photoemission.