Third order nonlinear susceptibility of InN at near band-gap wavelengths

Abstract

The authors report room-temperature measurements of the third order nonlinear susceptibility modulus ∣∣χ(3)∣∣∣χ(3)∣ of thick (∼600nm)(∼600nm) InN layers. Transmission measurements provide a room-temperature value for the optical band gap of the samples slightly above 1500nm1500nm. Third order nonlinear optical susceptibility has been measured using degenerate four wave mixing experiments at wavelengths near and above band gap. ∣∣χ(3)∣∣∣χ(3)∣ values of (4.2–10)×10−10esu(4.2–10)×10−10esu were measured at this wavelength range. The associated relaxation time of the generated population grating at 1500nm1500nm was measured. The obtained value of 4.8ps4.8ps is consistent with a nonradiative recombination mechanism.