Measurement of Pump-Induced Absorption and Refractive Index Changes in GaInAsP/InP Waveguides Using an Optical Loop Mirror Interferometer

摘要

We investigated the direct measurement of intensity-dependent refractive index changes in GaInAsP/InP ridge waveguides with ps-order pump pulses below the band gap using an optical loop mirror interferometer. The temporal response of the probe in GaInAsP (λ_g = 1410 nm) waveguides was shown to be instantaneous with respect to 4ps pump pulses. The intensity-dependent refractive index coefficient was measured to be -2.0 ± 0.6 x 10~(-12) cm~2/W. In addition, pump-induced absorption changes were studied.