Electron-electron scattering in far-infrared quantum cascade lasers.
نویسندگان
چکیده
A large depolarization shift indicates a strong nonequilibrium intersubband electron-electron scattering ~G! in tunneling structure. For a far-infrared subband separation D;10 meV, the rate G scales with the uppersubband occupation and is never significantly reduced by screening. Despite this nonradiative decay a finite population inversion can be maintained. Finally, the applied bias changes the wave-function symmetry so as to cause a dramatic variation of the electron-electron scattering rate.
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عنوان ژورنال:
- Physical review. B, Condensed matter
دوره 53 11 شماره
صفحات -
تاریخ انتشار 1996