Abstract

The conversion efficiency in second-harmonic generation of an amplified beam in a master-oscillator power amplifier copper-vapor laser (CVL) is lower than that of the oscillator beam alone. This lower efficiency is often vaguely attributed to wave-front degradation in the amplifier. We investigate the role of wave-front degradation and thermal dephasing in the second-harmonic generation of a CVL from a β-barium borate crystal. Choosing two beams with constant intrapulse divergence, one from a generalized diffraction filtered resonator master oscillator alone and other obtained by amplifying oscillator by use of a power amplifier, we show that at low flux levels the decrease in efficiency is due to wave-front degradation. At a fundamental power above the critical power for thermal dephasing, the decrease is due to increased UV absorption and consequent thermal dephasing. Thermal dephasing is higher for the beam with the lower coherence width.

© 2005 Optical Society of America

Efficient second harmonic generation in β-barium borate by a diffraction-limited copper vapor laser

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4.7-W, 255-nm source based on second-harmonic generation of a copper-vapor laser in cesium lithium borate

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Single-pulse time-resolved comparative study on the performance of a master-oscillator, power-amplifier copper-vapor-laser system with generalized diffraction-filtered and unstable resonators as master oscillators

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High-average-power (15-W) 255-nm source based on second-harmonic generation of a copper laser master oscillator power amplifier system in cesium lithium borate

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Thermal dephasing in an enhanced cavity based high-power second harmonic generation

Saeed Ghavami Sabouri and Alireza Khorsandi
Appl. Opt. 57(30) 9140-9147 (2018)