Generation of Broadband Tunable Coherent X-rays by Using Optical Field Induced Ionization

利用光场诱导电离产生宽带可调谐相干 X 射线

基本信息

批准号：
09450033
负责人：
SASAKI Wataru
金额：
$ 5.82万
依托单位：
Miyazaki University
依托单位国家：
日本
项目类别：
Grant-in-Aid for Scientific Research (B)
财政年份：
1997
资助国家：
日本
起止时间：
1997 至 1998
项目状态：
已结题

项目摘要

We have demonstrated vacuum ultraviolet emissions from pulsed rare gas jet excited by a high intensity ultrashort pulse laser. Various emission characteristics are investigated thoroughly. Ultrashort pulse Lasers are also used to control the dissociation process of alkali halide molecules in a femtosecond time scale. These knowledge should be used to develop a practical coherent x-ray source in the laboratory scale.As a result of the interaction of Ar and high intensity laser field, we have observed emissions from Ar_2^* at 126 nm for the first time together with some signals of high order harmonics. The focused laser intensity dependence of the Ar excimer intensity agrees well with that predicted by a tunnel ionization theory so called ADK theory. We, therefore, found out that the production of Ar excimers was initiated by high intensity laser produced electrons, which may become a substitution to those produced by an electron beam device.Experimental data show no difference in terms of the Ar excimer emission when linearly polarized and circularly polarized laser beams interacted with Ar. Considering about the energy transport of electrons in a high intensity laser produced plasma theoretically, we have found out a rapid conductive cooling of a plasma plays an important role for the excimer pioduction.The control of a molecule by using a high intensity laser has been demonstrated in the femtosecond time region as well. Alkali halide molecules have been excited and deexcited by using two different wavelength (ultraviolet and visible) lasers, which leads to the coherent control of the molecule with the minimum thermal effect This type of coherent molecular control means that the molecule can become a good optical amplifier even in a very short wavelength range, and can become a new coherent x-ray source.

我们已经证明了通过高强度超短脉冲激光器激发的脉冲稀有气流的真空紫外线排放。对各种排放特性进行了彻底研究。超短脉冲激光器还用于以飞秒时间尺度控制碱卤化物分子的解离过程。这些知识应用于在实验室量表中开发实用的连贯X射线源。由于AR和高强度激光场相互作用，我们首次观察到AR_2^*的排放量首次在126 nm处发射，以及一些高阶谐波信号。 AR准分子强度的聚焦激光强度依赖性与所谓的ADK理论的隧道电离理论所预测的相吻合。因此，我们发现，AR准分子的产生是由高强度激光产生的电子引发的，这可能成为电子束设备产生的电子的替代。实验性数据显示，当线性偏振和圆形极化激光束与AR相互作用时，AR精液发射的差异无差异。考虑到从理论上产生的血浆产生的电子激光器中电子的能量传输，我们发现血浆的快速导电冷却对准分子pioduction起着重要作用。使用高强度激光器在femtosececond时区域中证明了对分子的控制。通过使用两个不同的波长（紫外线和可见）激光器激发和去激发碱卤化物分子，从而导致分子与最小热效应对这种类型的相干分子控制的相干控制意味着分子可以成为一个很好的光学放大器，甚至可以在很短的波动范围内变得良好，并且可以成为一个新的cooter cooter feelent coothent sup cooter。