Third-order nonlinearities in GeSe2–In2Se3–CsI glasses for telecommunications applications

Ultrafast third-order nonlinear optical responses of GeSe2–In2Se3–CsI chalcohalide glasses have been measured by using optical Kerr effect (OKE) technique at 1064 nm. The obtained third-order nonlinear susceptibility χ(3) and nonlinear refractive index n2 are as large as 9.46 × 10−12 esu and 6.5 × 10−14 cm2/W, respectively. The relationship between glass compositions and the third-order nonlinear optical responses was analyzed by Raman spectra in terms of structural evolution. It is suggested that the tetrahedral units play an important role in the ultrafast third-order nonlinear optical responses of these chalcohalide glasses. The present glass is a promising material for all-optical switching devices.