Optical evidence of quantum well channel in low-temperature molecular beam epitaxy grown Ga(AsBi)/GaAs nanostructures, Yu. I. Mazur, V. G. Dorogan, M. Schmidbauer, G. G. Tarasov, S. R. Johnson, X. Lu, S-Q. Yu, Z. M. Wang, T. Tiedje, G. J. Salamo, Nanotechnology 22, 375703 (2011)
A Ga(AsBi) quantum well (QW) with Bi content reaching 6% and well width of 11 nm embedded in GaAs is grown by molecular beam epitaxy at low temperature and studied by means of high-resolution x-ray diffraction, photoluminescence (PL), and time-resolved PL. It is shown that for this growth regime, the QW is coherently strained to the substrate with a low dislocation density. The low temperature PL demonstrates a comparatively narrow excitonic linewidth of ∼ 40 meV. For high excitation density distinct QW excited states evolve in the emission spectra. The origins of peculiar PL dependences on temperature and excitation density are interpreted in terms of intra-well optical transitions.