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arXiv · 1301.5837

Gate controlled coupling of intersubband plasmons

Aymeric Delteil·Angela Vasanelli·Yanko Todorov·Bruno Paulillo·Giorgio Biasiol·Lucia Sorba·Carlo Sirtori
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Abstract

The optical response of a heavily doped quantum well, with two occupied subbands, has been investigated as a function of the electronic density. It is shown that the two optically active transitions are mutually coupled by dipole-dipole Coulomb interaction, which strongly renormalizes their absorption amplitude. In order to demonstrate this effect, we have measured a set of optical spectra on a device in which the electronic density can be tuned by the application of a gate voltage. Our results show that the absorption spectra can be correctly described only by taking into account the Coulomb coupling between the two transitions. As a consequence, the optical dipoles originating from intersubband transitions are not independent, but rather coupled oscillators with an adjustable strength.

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Aymeric Delteil, Angela Vasanelli, Yanko Todorov, Bruno Paulillo, Giorgio Biasiol, Lucia Sorba, Carlo Sirtori. 2013-01-24. Gate controlled coupling of intersubband plasmons. https://doi.org/10.1063/1.4788753

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