Kuipers, Jack and Waltner, Daniel and Petitjean, Cyril and Berkolaiko, Gregory and Richter, Klaus (2010) Semiclassical gaps in the density of states of chaotic Andreev billiards. Phys. Rev. Lett. 104, 027001.
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The connection of a superconductor to a chaotic ballistic quantum dot leads to interesting phenomena, most notably the appearance of a hard gap in its excitation spectrum. Here we treat such an Andreev billiard semiclassically where the density of states is expressed in terms of the classical trajectories of electrons (and holes) that leave and return to the superconductor. We show how classical orbit correlations lead to the formation of the hard gap, as predicted by random matrix theory in the limit of negligible Ehrenfest time _E, and how the influence of a finite _E causes the gap to shrink. Furthermore, for intermediate _E we predict a second gap below E =π/2_E which would presumably be the clearest signature yet of _E-effects.
|Date:||11 January 2010|
|Institutions:||Physics > Institute of Theroretical Physics > Chair Professor Richter > Group Klaus Richter|
|Subjects:||500 Science > 530 Physics|
|Refereed:||Yes, this version has been refereed|
|Created at the University of Regensburg:||Partially|
|Deposited On:||06 Aug 2009 07:06|
|Last Modified:||19 Jun 2012 15:32|