Absorption and emission of far-IR radiation by hot holes in GaAs/AlGaAs quantum wells

Abstract

It is found that when holes in GaAs/Al0.5Ga0.5As quantum wells are heated by a longitudinal electric field, the absorption in the far-IR region of the spectrum changes. The spontaneous emission spectrum in the far-IR range is measured. It is shown that the absorption and emission are due to direct intersubband transitions of holes near the peaks in the reduced density of states. The experimental data are in agreement with a theoretical calculation.