Saturation of the nonlinear refractive-index change in a semiconductor-doped glass channel waveguide

Abstract
The saturated nonlinear refractive‐index change in a CdSxSe1−x semiconductor‐doped glass channel waveguide was measured with a picosecond pump‐probe Mach–Zehnder interferometer at photon energies below the band gap. The pump‐probe configuration permitted the resolution of competing thermal and electronic nonlinearities. The significance of the results for all‐optical switching is discussed.