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arXiv · 1407.3923

Quantum model of coupled intersubband plasmons

Giulia Pegolotti·Angela Vasanelli·Yanko Todorov·Carlo Sirtori
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Abstract

We present a quantum model to calculate the dipole-dipole coupling between electronic excitations in the conduction band of semiconductor quantum wells. We demonstrate that the coupling depends on a characteristic length, related to the overlap between microscopic current densities associated with each electronic excitation. As a result of the coupling, a macroscopic polarization is established in the quantum wells, corresponding to one or few bright collective modes of the electron gas. Our model is applied to derive a sum rule and to investigate the interplay between tunnel coupling and Coulomb interaction in the absorption spectrum of a dense electron gas.

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Giulia Pegolotti, Angela Vasanelli, Yanko Todorov, Carlo Sirtori. 2014-07-15. Quantum model of coupled intersubband plasmons. https://doi.org/10.1103/physrevb.90.035305

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