Two-dimensional electron-hole liquid in single Si quantum wells with large electronic and dielectric confinement.
We report a luminescence study of the electronic properties of the 2D electron-hole liquid in crystalline Si quantum wells with SiO2 dielectric barriers. The Fermi-Dirac condensation of e-h pairs into a metallic liquid is strongly enhanced by spatial localization. We present experimental evidence for the formation of liquid nanodroplets, with size increasing with e-h pair density. The quantum confined regime is observed for well width below 15 nm. The data are analyzed in a confinement model that takes account of the band-gap renormalization by 2D many-body effects and the increase of the Coulomb interactions due to the dielectric mismatch between the Si well and the SiO2 barriers.
Pauc
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DRFMC/SP2M, CEA-Grenoble, 17 Avenue des Martyrs, 38054 Grenoble Cedex 9, France. pauc@drfmc.ceng.cea.fr
Calvo
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V
Eymery
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J
Fournel
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F
Magnea
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