Piezoelectric effects in ultrahigh quality AlGaAs/GaAs single quantum wire

Optical properties of V-shaped AlGaAs/GaAs single quantum wire with improved interface quality are investigated by means of photoluminescence (PL), PL excitation (PLE), and time-resolved PL measurements. Zero PLE absorption intensities are observed at low temperatures around ground state transitions. Excitation power density-dependent optical properties provide evidence that the zero PLE absorption intensities are due to an internal electric field created by the tiny strain-induced piezoelectric polarization along the wires, which causes complete spatial separation of the electron and hole wavefunctions along the wires.