Concentrated oscillator strength of one-dimensional excitons in quantum wires observed with photoluminescence excitation spectroscopy

Photoluminescence excitation spectra have been measured on a series of T-shaped quantum-wire (T-QWR) samples fabricated by the cleaved-edge overgrowth method with molecular-beam epitaxy, in which the lateral confinement is systematically changed. We have successfully evaluated the absorption area intensity of one-dimensional (1D) excitons, and found the concentration of oscillator strength into 1D exciton states with increased lateral confinement.