Nonlinear refraction and absorption properties of optical materials for high-peak-power long-wave-infrared lasers

Abstract

Optical materials transparent in the CO₂ laser wavelength range have been evaluated regarding their suitability for components in ultrashort-pulse (≤ a few ps), high-peak-power (≥ a few TW) long-wave infrared (LWIR) lasers. We provide values for the nonlinear refractive index (n₂) for seventeen materials, and thresholds for nonlinear absorption for eleven materials. Characterizations were performed using a 2 ps laser pulse at λ = 9.2 μm. This paper methodically presents the newly acquired data in conjunction with existing literature on linear optical properties, establishing it as a comprehensive reference for designing high-peak-power LWIR laser systems.