Electron hole liquid in silicon single quantum wells

We have carried out photoluminescence measurements on the two dimensional electron hole liquid in perfectly crystalline Si quantum wells with SiO2 barriers. The condensation of excitons in an EHL is strongly enhanced in 2D geometry. Formation of liquid nanodroplets with size varying with laser power is seen. Carriers are submitted to a quantum confinement regime for sufficiently small thickness. We present a model taking into account 2D many-body effects and the increase of the Coulomb interaction due to the dielectric mismatch between the Si well and the dielectric barrier. Results are in good agreement with photoluminescence measurements.