Interaction-induced chaos in a two-electron quantum dot system - art. no. 115313

A quasi-one-dimensional quantum dot containing two interacting electrons is analyzed in search of signatures of chaos. The two-electron energy spectru m is obtained by diagonalization of the Hamiltonian including the exact Cou lomb interaction. We find that the level-spacing fluctuations closely follo w a Wigner-Dyson distribution, which indicates the emergence of quantum sig natures of chaos due to the Coulomb interaction in an otherwise nonchaotic system. In general, the Poincare maps of a classical analog of this quantum -mechanical problem can exhibit a mixed classical dynamics. However, for th e range of energies involved in the present system, the dynamics is strongl y chaotic, aside from small regular regions. The system we study models a r ealistic semiconductor nanostructure, with electronic parameters typical of gallium arsenide.