Morphological and temperature-dependent optical properties of InAs quantum dots on GaAs nanowires with different InAs coverage

Abstract

We report a study on the morphological and temperature-dependent optical properties of InAs quantum dots on GaAs nanowires with different InAs coverage. We find that the size, density, and distribution of quantum dots strongly depend on the InAs coverage. At higher coverage, the quantum dots exhibit a longer peak wavelength and broader linewidth at low temperature, suggesting a larger size and increased size fluctuations. Particularly, a great difference in the linewidth dependence on temperature for different InAs coverage is observed, corresponding to a different result of competition between electron-phonon scattering and thermal penetration of carriers between neighboring quantum dots.