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arXiv · cond-mat/9704150

Far-infrared edge modes in quantum dots

Abstract

We have investigated edge modes of different multipolarity sustained by quantum dots submitted to external magnetic fields. We present a microscopic description based on a variational solution of the equation of motion for any axially symmetric confining potential and multipole mode. Numerical results for dots with different number of electrons whose ground-state is described within a local Current Density Functional Theory are discussed. Two sum rules, which are exact within this theory, are derived. In the limit of a large neutral dot at B=0, we have shown that the classical hydrodynamic dispersion law for edge waves ω(q) \sim \sqrt{q \ln (q_0/q)} holds when quantum and finite size effects are taken into account.

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E. Lipparini, N. Barberan, M. Barranco, M. Pi, Ll. Serra. 1997-05-15. Far-infrared edge modes in quantum dots. https://doi.org/10.1103/physrevb.56.12375

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