Highly nonlinear GeS_2-based chalcohalide glass for all-optical twin-core-fiber switching

A new GeS2-based chalcohalide glass was synthesized by the melt-quenching technique for nonlinear optical applications. A large glass-forming region was defined, and a wide infrared transmission was measured. Marked optical third-order nonlinearity was measured (n2≈7.5×10-5 cm2/GW), making this glass one of the best candidates for ultrafast nonlinear optical applications. All-optical switching in the second telecommunication window (λ=1.31 μm) by control of the optical pulse intensity in a twin-core-fiber directional coupler was numerically modeled, and a crossover length of 9.25 mm was calculated.