Ga‐Sb‐S‐I chalcohalide glasses and fibers for mid‐infrared applications

Abstract

In this work, environment friendly Ga‐Sb‐S‐I chalcohalide glasses and fibers are developed for mid‐infrared applications. The developed Ga8Sb32S60‐xIx (x = 0‐10) glasses have a transmission window of ~0.7‐14 µm, linear refractive indices (n0) of ~ 2.690‐2.751 at 1.55 µm, nonlinear refractive indices (n2) of ~10.5‐12.4 × 10−14 cm2/W at 1.55 µm, and zero dispersion wavelengths (λ0) of ~4.94‐5.25 µm. The developed Ga8Sb32S55I5/Ga8Sb31S56I5 (core/cladding) fiber can transmit infrared light from below 2 µm to ~8 µm, and shows the minimum loss of ~1.2 dB/m at ~6 µm. The wide transmission window, high optical nonlinearity and superior thermal stability against crystallization of the glasses, and the good 2‐8 µm transmission property of the fiber make these materials promising for mid‐infrared applications such as thermal imaging, nonlinear optics, and laser transmission.