Third-order nonlinear optical properties of As2S3 chalcogenide glass

Abstract

Third-order nonlinear optical properties of As2S3 chalcogenide bulk glass are studied experimentally. Third-harmonic generation (THG) measurement shows the value of the third-order susceptibility χ(3) to be 5.6×10−19 m2/V2 (1.0×10−11 esu) at the funda- mental-light wavelength of 2.1 μm. This value is more than 300 times that for a silica glass. The dependence of the THG χ(3) on the wavelength has been measured, which indicates the χ(3) enhancement effect due to three-photon resonance. Optical Kerr shutter operation is also achieved using the chalcogenide glass. The nonlinear refractive index of n2=6.8×10−18 m2/W is obtained at the gate-light wavelength of 700 nm. This value of n2 agrees with that estimated from the THG measurement. Other nonlinear effects such as two-photon absorption for the gate light are discussed.