GaxIn1−xP multiple-quantum-wire heterostructures prepared by the strain induced lateral layer ordering process

Abstract
We report the in situgrowth of Ga x In1−x P multiple‐quantum‐wire (MQWR) structures by gas sourcemolecular beam epitaxy. The MQWRs were formed through a strain induced lateral layer ordering (SILO) process occurring spontaneously when (GaP) n /(InP) n short‐period superlattices were grown on (100)‐oriented on‐axis GaAs substrates. In one sample, cross‐sectional transmission electron microscopy estimated average quantum‐wire cross sections of 50 Å×100 Å with lengths of over 3000 Å leading to a linear density of 100 wires/μm. The existence of the MQWRs is also supported by polarized photoluminescencespectroscopy. Anisotropy ratios for two orthogonal polarizations were measured to be an order of magnitude larger than any previously reported. These data support the existence of MQWRs and demonstrate that the SILO growth process is a consistent and reproducible method of MQWR fabrication.