English

Controlling the Sign of Magnetoconductance in Andreev Quantum Dots

Mesoscale and Nanoscale Physics 2009-12-16 v2 Superconductivity Chaotic Dynamics

Abstract

We construct a theory of coherent transport through a ballistic quantum dot coupled to a superconductor. We show that the leading-order quantum correction to the two-terminal conductance of these Andreev quantum dots may change sign depending on (i) the number of channels carried by the normal leads or (ii) the magnetic flux threading the dot. In contrast, spin-orbit interaction may affect the magnitude of the correction, but not always its sign. Experimental signatures of the effect include a non-monotonic magnetoconductance curve and a transition from an insulator-like to a metal-like temperature dependence of the conductance. Our results are applicable to ballistic or disordered dots.

Keywords

Cite

@article{arxiv.0908.0666,
  title  = {Controlling the Sign of Magnetoconductance in Andreev Quantum Dots},
  author = {Robert S. Whitney and Ph. Jacquod},
  journal= {arXiv preprint arXiv:0908.0666},
  year   = {2009}
}

Comments

Final version (4pages 3figs)- improved presentation and fig 3, and updated references