Abstract
An effective mobility edge for excitons in two-dimensional systems is shown to exist by comparing photoluminescence (PL) and PL excitation (PLE) with excitation-energy-dependent micro-PL spectra. The effective mobility edge of excitons shifts towards higher energies with increasing potential fluctuations. This blue shift is correlated with a sharp decrease of the PLE signal resulting in an extremely large energy separation between the PL and PLE spectra. Numerical simulations using a random potential confirm these results and predict a significant deviation of the PLE from the absorption spectrum.
- Received 2 July 1997
DOI:https://doi.org/10.1103/PhysRevB.56.R4387
©1997 American Physical Society