We report on the study of many-body interactions in a single high quality V-shaped quantum wire by means of continuous and time-resolved microphotoluminescence. The transition from a weakly interacting exciton gas when the carrier density n is less than 10^5 cm^-1 (i.e. n aX < 0.1, with aX the exciton Bohr radius), to a dense electron-hole plasma (n > 10^6 cm^-1, i.e. n aX > 1) is systematically followed in the system as the carrier density is increased. We show that this transition occurs gradually : the free carriers first coexist with excitons for n aX > 0.1, then the electron-hole plasma becomes degenerate at n aX = 0.8. We also show that the non-linear effects are strongly related to the kind of disorder and localization properties in the structure especially in the low density regime.
@article{arxiv.cond-mat/0301229,
title = {Mott transition from a diluted exciton gas to a dense electron-hole plasma in a single V-shaped quantum wire},
author = {Thierry Guillet and Roger Grousson and Valia Voliotis and Michel Menant and Xue-Lun Wang and Mutsuo Ogura},
journal= {arXiv preprint arXiv:cond-mat/0301229},
year = {2007}
}