Subpicosecond carrier lifetimes in GaAs grown by molecular beam epitaxy at low substrate temperature

Abstract

Time-resolved photoluminescence transients of low-temperature molecular beam epitaxially grown GaAs layers have been measured with femtosecond temporal resolution and compared with numerical Monte Carlo calculations. It has been shown that the shape of these transients measured at different emission energies is determined not only by the carrier lifetime but also by the electron redistribution in the conduction band. Analysis of the experimental results yields the carrier lifetime in the investigated samples of 400 fs.