New Journal of Physics

Modeling of open quantum dots and wave billiards using imaginary potentials for the source and the sink

Karl‐Fredrik Berggren, Irina I. Yakimenko, Jani Hakanen

Published Jul 5, 2010• 19 citations

Abstract

A heuristic model for particle states and current flow in open ballistic two-dimensional (2D) quantum dots/wave billiards is proposed. The model makes use of complex potentials first introduced in phenomenological nuclear inelastic scattering theory (the optical model). Here we assume that external input and output leads connecting the system to the source and the drain regions may be represented by complex potentials. In this way, a current may be set up between the two 'pseudo-leads'. Probability densities and current flows for an open quantum dot are analyzed here numerically and the results are compared with the microwave measurements used to emulate the system. The model is of conceptual as well as practical interest. In addition to quantum billiards, it may be used as a tool per se to analyze transport in classical wave analogues, such as microwave resonators, acoustic resonators, effects of leakage on such systems, etc.

DOI: 10.1088/1367-2630/12/7/073005

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