Atomic absorption of thermally dissociated iodine for laser applications

Abstract

An absorption cell for the 1.315 mu m iodine laser wavelength has been constructed using thermal dissociation of molecular iodine vapour to produce ground-state iodine atoms. Measurements of the small-signal absorption coefficient for iodine pressures up to 5 Torr and temperatures up to 750 degrees C have been compared with the predictions of a simple thermodynamic model of the iodine dissociation equilibrium, and satisfactory agreement obtained. The model readily allows calculation of operating conditions required for the use of the iodine absorber as a saturable absorber, for free-induction decay pulse generation and for coherent pulse propagation experiments.