Guided-wave measurement of the 1.06-μm two-photon absorption coefficient in GaAs epitaxial layers

Abstract

The optical perturbation of an infrared wave guided in a GaAs epitaxial layer allows us to measure the two-photon absorption coefficient β for the wavelength λ=1.06 μm. The use of optical properties of free carriers induced by the two-photon effect and of guided optical wave techniques strongly enhances method accuracy. The result (β=0.06 cm MW−1) is in good agreement with the most recent bulk measurements and the theoretical values.