快速Z箍缩时毛细管放电软X射线尖峰的激光特性

Lasing Characteristic of Soft X-Ray Spike Pumped by Capillary Discharge at Fast Z-Pinch

在低气压(25 Pa)快电流前沿(27 ns)下,利用镀金X射线二极管(XRD)测量获得了毛细管放电软X射线激光尖峰输出。研究该软X射线激光输出特性,为其未来的应用打下基础。低气压和快前沿导致等离子体的快速箍缩,此时激光产生于背景光峰值附近,脉宽1.6 ns。实验测量了快速Z箍缩时激光的束散角和增益特性。采用小孔扫描法,测得激光束散角为5.3 mrad。通过改变增益介质长度的方法,测得介质的增益系数为0.45 cm-1,最大的增益长度积为8.28。此外利用单色仪在46.9 nm处测得了激光尖峰输出。

Laser spike of soft X-ray pumped by capillary discharge is measured at 25 Pa pressure and 27 ns rise time of the current pulse with X-ray diode （XRD） coated with a gold layer. The characteristic of this laser is studied. The low pressure and the short rise time of the current pulse lead to a fast compression of the plasma. In this condition, the laser spike with the duration of 1.6 ns near the peak of the ground light is obtained. The angle of divergence and gain coefficient of the spike at fast Z-pinch are measured. The angle of divergence measured by shifting the pinhole is 5.3 mrad. By changing the length of gain medium, the gain coefficient is measured as 0.45 cm^-1 and gain-length product as 8.28. In addition, a monochromator is used and the laser spike about 46.9 nm is observed.