Abstract

Barium vapour lasers (BVLs) are an efficient (~0.5%), high average power (10-15 W) and high pulse rate (~10 kHz) source operating on a variety of near and mid IR wavelengths (1.13, 1.50, 2.55, and 4.72 microns), with applications including scanning ranging, remote gas detection, and optical fibre testing. The BVL is also an amenable system for studying kinetics of metal vapour lasers, as the atom and ion ground states have visible upward transitions suitable for hook spectroscopy. To date, there has been relatively little work on ground state kinetic issues and the factors influencing prepulse ground state density in metal vapour laser (MVL) systems in general are not fully understood. Previous reports^1,2,3 indicate that the observed prepulse metal atom density across the tube bore is well below that expected from thermal considerations. We have studied the factors influencing the pre-pulse ground state density for a BVL operating with both helium and neon buffer gases.

© 1994 IEEE