RAMAN-SCATTERING ANALYSIS OF INAS GASB ULTRATHIN-LAYER SUPERLATTICES GROWN BY MOLECULAR-BEAM EPITAXY/

Raman scattering analysis has been performed to study characteristic p honon modes in InAs/GaSb ultrathin-layer superlattices (ULSs) grown by molecular beam epitaxy. Either interface bond InSb or GaAs was select ively made in the ULSs by controlling the beam supply sequence during growth. In addition to the acoustic and optic phonons modulated by ULS structure, the Raman spectra were composed of two different types of new phonon mode localized at each interface of InSb or GaAs. These exp erimental data have been understood in agreement with the theoretical analysis.