Efficient compact watt-level deep-ultraviolet laser generated from a multi-kHz Q-switched diode-pumped solid-state laser system

Abstract

Stable high-power operation in the deep ultraviolet is achieved from a multi-kHz diode-pumped multi-longitudinal-mode Q-switched Nd:YAG laser by fourth harmonic generation in an external resonant cavity and by fifth harmonic generation using sum-frequency mixing of the fourth harmonic and the residual fundamental in a beta-BBO crystal. Over 2.1 W of 266 nm radiation and 540 mW of 213 nm radiation were generated from a fundamental power of 7 W of 1064 nm light at 5 kHz. The overall conversion efficiency from IR to deep ultraviolet at 213 nm is larger than 7.5%. (C) 2002 Elsevier Science B.V. All rights reserved.