Initiation techniques and the vacuum-ultraviolet-radiation efficiency of a stabilized multichannel surface discharge

Multichannel surface discharges possess a number of advantageous characteristics for the optical pumping of photochemically driven lasers. This work reports on a type of large-area low-inductance sources of intense UV-VUV (vacuum-ultraviolet) radiation based on spatially stabilized multichannel discharges in gases. The discharges consist of several dozens of closely located parallel plasma channels initiated synchronously along a dielectric surface on the area of several hundred square centimeters. In comparison with a large-area diffuse surface discharge, the plasma confinement within relatively thin channels greatly improves the efficiency of the discharge emission in the VUV spectral range. Several techniques are introduced, which allow a synchronous formation and homogeneous development of multiple spatially stabilized discharge channels. Technical efficiency of the discharge radiation within the spectral range of 120-200 nm reaches 5% and an effective brightness temperature of the radiating plasma exceeds 20 kK. Synchronous operation of a number of multichannel discharge modules producing high-intensity submicrosecond optical pulses is demonstrated, which is of importance for the pump source scaling and geometrical adaptation. (c) 2006 American Institute of Physics.