Optical Investigations of the Sidewall Recombination in Wet Etched InGaAs/InP-Wires

Abstract

We have investigated the optical properties of wet chemically etched InP/InGaAs-wires with widths between 100 nm and 10 µm for a wide range of excitation densities and energies. We observe that the non radiative recombination centers at the etched sidewalls can be saturated already at moderate excitation densities of 100 W/cm2. Avoiding saturation effects we obtain a surprisingly large sidewall recombination velocity of 107 cm/s at 77 K. The comparison of luminescence measurements at excitation energies above and below the InP band gap energy shows, that the non radiative recombination centers are located in the InGaAs quantum well.