Polarization-resolved optical absorption in single V-groove quantum wires

Abstract
Optical transitions associated with all three linear polarization directions were investigated in single GaAs V-groove quantum wires of different wire thicknesses. This was accomplished by combining absorption measurements in V-groove waveguide geometry with surface-excited photoluminescence excitation spectroscopy. The observed transitions were identified with the aid of model calculations. It is shown that excitonic intersubband coupling should be accounted for in order to explain the optical transitions associated with confined light-hole-like states. The results are relevant for the design of efficient quantum wire waveguide modulators and lasers.