Photoluminescence from electron-hole plasmas confined in Si/Si1-xGex/Si quantum wells
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چکیده
We report the first observation of photoluminescence from electron-hole plasmas in Si/S&,sGe&Si quantum wells. While at liquid helium temperature, luminescence due to shallow bound excitons is observed. At 77 K electron-hole plasma (EHP) luminescence dominates the spectra over a wide range of pump powers. Convolution of the occupied electron and hole densities of states gives an excellent fit to the photoluminescence line shape. A bandgap reduction of up to 15 meV at high carrier densities is observed for wide quantum wells, but no such shift is detected for narrow quantum wells.
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تاریخ انتشار 1999