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Interaction-induced chaos in a two-electron quantum-dot system

A. J. Fendrik·M. J. Sánchez·P. I. Tamborenea
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Abstract

A quasi-one-dimensional quantum dot containing two interacting electrons is analyzed in search of signatures of chaos. The two-electron energy spectrum is obtained by diagonalization of the Hamiltonian including the exact Coulomb interaction. We find that the level-spacing fluctuations follow closely a Wigner-Dyson distribution, which indicates the emergence of quantum signatures of chaos due to the Coulomb interaction in an otherwise non-chaotic system. In general, the Poincaré maps of a classical analog of this quantum mechanical problem can exhibit a mixed classical dynamics. However, for the range of energies involved in the present system, the dynamics is strongly chaotic, aside from small regular regions. The system we study models a realistic semiconductor nanostructure, with electronic parameters typical of gallium arsenide.

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A. J. Fendrik, M. J. Sánchez, P. I. Tamborenea. 2000-09-06. Interaction-induced chaos in a two-electron quantum-dot system. https://doi.org/10.1103/physrevb.63.115313

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