Impact of fs and ns pulses on indium and sulfur doped gallium selenide crystals

The impact of fs and ns pulses on indium and sulfur doped gallium selenide crystals with four and five different doping concentrations, respectively, has been studied in comparison with that of undoped GaSe. The inconsistence of the visual criterion of the damage threshold determination has been demonstrated. The multiphoton absorption and thermal effect have been identified as key factors limiting fs and ns pulse pump intensities, respectively. High advantages in the limit pump intensity as up to 50% for optimally indium-doped crystal and up to 4.5 times for optimally sulfur-doped crystal have been demonstrated under fs pulses expose.