Description
The soft X-ray (46.9 nm) Ne-like argon laser driven by capillary Z-pinch discharges is a promising source for a wide range of scientific and practical applications. Conventionally, the excitation system that produces the required hot, dense plasma relies on high-voltage (0.1-0.8 MV) Marx generators. Recently, we demonstrated a Marx-generator-free 46.9-nm laser operating at a low voltage (U = 35-45 kV) by exploiting the bifilar effect [IEEE Trans. Plasma Sci. 52, 4786-4793 (2024)]. The laser employs a C-C excitation circuit with a magnetic switch compressor, a configuration commonly used in ordinary TEA XeCl excimer lasers. Owing to the low operating voltage, the system is simple, compact, and not expensive. This type of Ar8+ ion laser is therefore well suited for applications in small educational and research laboratories. The laser generates 46.9 nm pulses with energies of up to 4 μJ. In the present study, we identify excitation parameters of low-voltage capillary discharges that enable a further increase in the laser pulse energy. These parameters are determined using a comprehensive laser model that combines atomic-kinetic and ray-tracing codes with a one-fluid, two-temperature, one-dimensional magnetohydrodynamic model of capillary Z-pinches. The plasma model is coupled to an electrical circuit interface implemented in COMSOL Multiphysics.