Investigation of dual-wavelength pump schemes for optically pumped rare gas lasers

Optically pumped rare gas lasers (OPRGLs) have shown great potential to generate high energy laser radiation with high beam quality. As an alternative to the diode-pumped alkali vapor lasers (DPALs), they have similar working principles and characteristics, but OPRGLs have the advantage that the gain medium is chemically inert and is appropriate for closed-cycle operation. One of the challenges OPRGLs are faced with is the bottleneck caused by the slow 1s₄-1s₅ collisional relaxations at room temperature. A 1s₄-2p₁₀ dual-wavelength pump method had been proposed to transfer the populations pooled on the 1s₄ level to the lasing cycle using a steady-state laser model. We explored this method further through 1s₄-2p₈ and 1s₄-2p₇ dual-wavelength pump schemes. The enhancement efficiencies at room temperature for a repetitively pulsed discharge, CW dual-wavelength pump system were examined using a dynamic model, and an experiment with a pulsed secondary pump was conducted for qualitative evaluations.