On the Amplification Capability of Ne-like Ar Soft X-ray Laser Generated by Capillary Z-Pinch Discharge

We have studied the gain characteristics of an Ne-like Ar soft X-ray (SXR) laser, at a relatively low discharge current, generated by a capillary z-pinch discharge, by changing the plasma length and the gas pressure. It was found that the pressure range of laser amplification varies with plasma length, which then yields different values of the gain at different pressures. For this reason, we suggest a quantity of “the gain-length product at the pressure of maximum laser output”. This quantity is suitable for comparing the amplification capability of soft X-ray laser devices, which use capillary discharge.