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Complex permittivity of a biased superlattice

A. Hernández-Cabrera·P. Aceituno·F. T. Vasko
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Abstract

Intersubband response in a superlattice subjected to a homogeneous electric field (biased superlattice with equipopulated levels) is studied within the tight-binding approximation, taking into account the interplay between homogeneous and inhomogeneous mechanisms of broadening. The complex dielectric permittivity is calculated beyond the Born approximation for a wide spectral region. A detectable gain below the resonance is obtained for the low-doped $GaAs$-based biased superlattice in the THz spectral region. Conditions of the stimulated emission regime for metallic and dielectric waveguide structures are discussed.

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A. Hernández-Cabrera, P. Aceituno, F. T. Vasko. 2007-07-05. Complex permittivity of a biased superlattice. https://doi.org/10.1063/1.2829820

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