Study of elementary processes for the lower laser level of the copper vapor laser

铜蒸气激光器低激光能级基本工艺研究

基本信息

批准号：
05452196
负责人：
GOTO Toshio
金额：
$ 4.42万
依托单位：
Nagoya University
依托单位国家：
日本
项目类别：
Grant-in-Aid for General Scientific Research (B)
财政年份：
1993
资助国家：
日本
起止时间：
1993 至 1994
项目状态：
已结题

来源：
https://kaken.nii.ac.jp/en/grant/KAKENHI-PROJECT-05452196/
关键词：
Cu metastable atoms diffusion coefficient electron collisional de-excitation saturated absorption spectroscopy copper vapor laser laser absorption spectroscopy 銅原子拡散定数

项目摘要

In the powerful and highly efficient copper vapor laser, the lower levels of the laser transitions are metastable states. The detailed knowledge of their relaxation processes is therefore of practical importance to improve the laser performance. In this study the diffusion and electron-collisional de-excitation processes for the metastable copper atoms were investigated, which determine the lifetime of the metastable atoms in the discharge.Copper vapor was produced in a discharge tube with a copper hollow cathode by cathodic sputtering. The diffusion coefficients for metastable copper atoms in Ne and Ar were determined from their density decay in the afterglow measured by using laser absorption spectroscopy. The diffusion coefficients for ground-state copper atoms in He, Ne, Ar were also determined by using absorption spectroscopy with a copper hollow cathode lamp used as a light source. It was found that the diffusion coefficients for the metastable and the ground-state copper atoms w … More ere essentially of the same magnitude, contrary to a reported result.A new method was developed to determine the lifetimes of metastable atoms in a steady-state discharge. The method is based on saturated absorption spectroscopy, in which a strong pump laser beam excites metastable atoms and a weak probe beam measures the reduction of their population due to the pump beam ; the analysis of the results with the aid of rate equations enables one to determine the lifetime of the metastable atoms. As was demonstated by experiments, the long lifetime of metastable atoms prevents the pump beam from causing hole burning in the velocity distribution of the atoms through collisional mixing of the populations with different velocities ; this allows one to use the rate-equation analysis. The obtained lifetime of the metastable copper atoms decreased with increasing discharge current. This indicates that their lifetime is mainly determined by electron-collisional destruction rather than by diffusion. This method of determining metastable-atom lifetime can be combined with electron density and temperature measurements to yield de-excitation rate constant for metastable atoms. Less

在功能强大且高效的铜蒸气激光器中，激光过渡的较低级别是亚稳态状态。因此，对他们放松过程的详细了解对于改善激光性能至关重要。在这项研究中，研究了对亚稳定铜原子的扩散和电子 - 授文去激发过程，这确定了放电中亚稳定原子的寿命。蒸发蒸气是通过阴极溅射在带有铜中空阴极的排放管中产生的。通过使用激光抽象光谱法测得的余辉中的NE和AR中亚稳定铜原子的差异系数。还通过使用抽象光谱与用作光源的铜空阴极灯使用抽象光谱法确定了HE，NE，AR中地面铜原子的差异系数。发现在稳态放电中开发了一种新方法来确定一种新的方法来确定一种新方法来确定一种新方法，从而确定一种新方法，因此发现了亚稳态和地面铜原子的差异系数。该方法基于饱和的抽象光谱，其中强泵激光束激发了亚稳态原子，而弱探头束可以测量由于泵束而导致其种群的减少。借助速率方程式对结果的分析使一个人能够确定亚稳定原子的寿命。正如实验揭示的那样，亚稳定原子的长寿命可防止泵束通过不同速度的种群的碰撞混合而导致原子速度分布的孔燃烧。这允许人们使用速率方程分析。亚稳态铜原子的寿命随着排放电流的增加而降低。这表明它们的寿命主要取决于电子 - 倾斜的破坏，而不是通过扩散确定。这种确定亚稳定原子寿命的方法可以与电子密度和温度测量结果结合使用，以产生亚稳态原子的降低速率常数。较少的