Far-infrared absorption in parallel quantum wires with weak tunneling

T. V. Shahbazyan; S. E. Ulloa

doi:10.1103/physrevb.54.16749

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arXiv · cond-mat/9606027

Far-infrared absorption in parallel quantum wires with weak tunneling

T. V. Shahbazyan·S. E. Ulloa

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Abstract

We study collective and single-particle intersubband excitations in a system of quantum wires coupled via weak tunneling. For an isolated wire with parabolic confinement, the Kohn's theorem guarantees that the absorption spectrum represents a single sharp peak centered at the frequency given by the bare confining potential. We show that the effect of weak tunneling between two parabolic quantum wires is twofold: (i) additional peaks corresponding to single-particle excitations appear in the absorption spectrum, and (ii) the main absorption peak acquires a depolarization shift. We also show that the interplay between tunneling and weak perpendicular magnetic field drastically enhances the dispersion of single-particle excitations. The latter leads to a strong damping of the intersubband plasmon for magnetic fields exceeding a critical value.

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T. V. Shahbazyan, S. E. Ulloa. 1996-06-05. Far-infrared absorption in parallel quantum wires with weak tunneling. https://doi.org/10.1103/physrevb.54.16749

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