Due to their broad transparency window in the infrared (IR) and high refractive index, chalcogenide glasses have a wide range of applications from biochemical sensing and integrated photonics, to fibers and imaging, to sensing and detection systems. To date, most work regarding laser-induced damage of chalcogenides has focused on pulsed laser damage. Here, we report the method and measurement of the continuous wave (CW) laser-induced damage threshold (LIDT) of chalcogenide glasses, Amorphous Materials AMTIR-1 (Ge33As12Se55), AMTIR-2 (As38Se62), AMTIR-5(AsxxSeyy) and AMTIR-7 (AsxxSeyy) at 1.07 µm. Following the International Organization for Standardization (ISO) 11254 and 21254 standards as best as possible, these measurements are made focusing 1.07 µm light to a spot size with 1/e2 diameter of 830 µm with an exposure of 5 seconds. Since the standards state that CW damage varies linearly with the spot size rather than area, it is reported in terms of the linear power density (LPD) instead of the irradiance, though the spot size must also be reported.
Furthermore, simulations of the temperature distribution resulting from the laser absorption is modeled solving two partial differential equations using COMSOL Multiphysics and includes temperature dependent parameters. The simulations were run for various irradiances to determine the expected CW LIDT of the two materials.
The continuous wave laser-induced damage thresholds of Schott chalcogenide glasses, IRG-24, IRG-25, and IRG-26, are measured for a 5s exposure of 1.07 μm light focused to a spot size with 1/e2 diameter of 830 μm, following the International Organization for Standardization standards.