GROWTH AND CHARACTERIZATION OF SERPENTINE SUPERLATTICES IN THE GASB-ALSB SYSTEM

We report the growth of GaSb/AlSb serpentine superlattices (SSLs) on v icinal GaAs and GaSb substrates. Cross-sectional transmission electron microscopy confirms the SSL structure and shows excellent lateral uni formity, better than previous arsenide-SSLs. Photoluminescence (PL) me asurements indicate a good-quality lateral superlattice with a spectra l linewidth between 13 and 15 meV. Polarization-dependent PL measureme nts give a normalized linear polarization around 60%, the strongest th at has been seen for SSL structures. Preliminary estimates suggest muc h better segregation between the Ga-rich and Al-rich regions than arse nide-SSLs, with the change in aluminum concentration DELTAx almost-equ al-to 0.35.