Optical characterization of InGaAs/InP quantum wire overgrowth by hydride VPE with InP

We have investigated the optical properties of InGaAs/InP quantum wires prior to and after hydride VPE overgrowth. Hydride VPE is a particularly efficient overgrowth technique as it permits overgrowths with semiinsulating InP at large growth rates without leaving any voids. With this technique, a homogeneous and smooth surface was achieved. PL measurements of the overgrown wires with widths between 500 nm and 18 nn showed a significant increase of the luminescence intensities of up to one order of magnitude after overgrowth and a corresponding decrease of the side wall recombination velocity of up to two orders of magnitude. In addition, the radiative lifetimes of the wires below 100 nm are significantly increased after the overgrowth and are raised above the value of a 2D reference sample