Many-body effects on intersubband resonances in narrow InAs/AlSb quantum wells |
| |
Authors: | Jianzhong Li C Z Ning |
| |
Institution: | Center for Nanotechnology, NASA Ames Research Center, M/S N229-1, Moffett Field, CA 94035, USA |
| |
Abstract: | Intersubband polarization couples to collective excitations of the interacting electron gas confined in a semiconductor quantum well (QW) structure. Such excitations include correlated pair excitations (repellons) and intersubband plasmons. The oscillator strength of intersubband resonances (ISBRs) strongly varies with QW parameters and electron density because of this coupling. Using the intersubband semiconductor Bloch equations for a two-conduction-subband model, we show that intersubband absorption spectra for narrow wells are dominated by the Fermi-edge singularity (via coupling to repellons) when the electron gas becomes degenerate and in the presence of large nonparabolicity. Thus the resonance peak position appears at the Fermi edge and the peak is greatly narrowed, enhanced, and red shifted as compared to the free particle result. Our results uncover a new perspective for ISBRs and indicate the necessity of proper many-body theoretical treatment in order for modeling and prediction of ISBR line shape. |
| |
Keywords: | Intersubband resonance Quantum wells Nonparabolicity Many-body effects |
本文献已被 ScienceDirect 等数据库收录! |
|