Eur. Phys. J. D 63, 3-8 (2011)
https://doi.org/10.1140/epjd/e2010-00256-7

Regular Article

Charge transfer statistics and entanglement in normal-quantum dot-superconductor hybrid structures

Institut für Theoretische Physik, Ruprecht-Karls-Universität Heidelberg, Philosophenweg 19, 69120 Heidelberg, Germany

^a e-mail: hsoller@googlemail.com
^b e-mail: komnik@uni-heidelberg.de

Received: 1 July 2010
Received in final form: 6 August 2010
Published online: 1 October 2010

Abstract

We analyze the full counting statistics (FCS) of a single-site quantum dot coupled to multiple metallic electrodes in the normal state and a superconductor for arbitrary transmission. We present an analytical solution of the problem taking into account the full energy dependence of the transmission coefficient. We identify two transport processes as sources of entanglement between the current carriers by observing positive cross current correlations. Furthermore, we consider ferromagnetic electrodes and show how they can be used as detectors in experiments violating the Bell-Clauser-Horne-Shimony-Holt inequality.