Polarized optical properties of a GaInP lateral superlattice

We report the optical properties of (GaP) ₁/(InP) ₁ short-period superlattice (SPS) structures in the presence of lateral composition modulation (LCM). LCM is related to alternating Ga-rich and In-rich GaInP bands elongated along the [11̄0] direction. Polarized photoluminescence (PL) measurements exhibit a strong anisotropy in the presence of LCM. Polarization anisotropy in a PL response is not observed for a sample in which no LCM forms. Raman spectra taken from the top surface of the sample exhibit a GaP-like longitudinal optical (LO) phonon response at 383 cm ^-1, an InP-like LO phonon response at 363 cm ^-1, and a transverse optical (TO) phonon response at 330 cm ^-1. The LO-like and the TO-like characteristics of these phonon modes are further investigated by taking Raman spectra from the cleaved edge of the sample in various polarization configurations.