CuH and CuBr absorption measurements and consequences on copper seeding in a Cu–HBr laser medium

International audienceMolecular absorption measurements have been made across the tube radius and with respect to time in a Cu–HBr laser media. CuBr and CuH relative densities in their fundamental levels are found from spectra around 428 and 434 nm. CuBr density decreases from the wall to zero absorption on the axis with a steep gradient at 15 mm from the axis. Inversely, CuH is present on the axis and its absorption decreases toward the wall. Dissociation of the CuH molecules in different excited levels can explain the temporal and radial increase of the copper ground-state density in our operating conditions in a Cu–HBr laser