Quantum signature blurred by disorder in indirect exciton gases
ICFO-Institut de Ciències Fotòniques, Mediterranean Technology Park - Av. del Canal Olímpic, E-08860 Castelldefels, Spain, EU
2 Laboratoire de Photonique et Nanostructures, CNRS - Route de Nozay, 91460 Marcoussis, France, EU
Accepted: 20 December 2010
The photoluminescence dynamics of a microscopic gas of indirect excitons trapped in coupled quantum wells is probed at very low bath temperature (≈350 mK). Our experiments reveal the non-linear energy relaxation characteristics of indirect excitons. Particularly, we observe that the excitons dynamics is strongly correlated with the screening of structural disorder by repulsive exciton-exciton interactions. For our experiments where two-dimensional excitonic states are gradually defined, the distinctive enhancement of the exciton scattering rate towards lowest-energy states with increasing density does not reveal unambiguously quantum statistical effects such as Bose stimulation.
PACS: 78.67.De – Quantum wells
© EPLA, 2011