Issue
EPL
Volume 87, Number 4, August 2009
Article Number 47002
Number of page(s) 6
Section Condensed Matter: Electronic Structure, Electrical, Magnetic and Optical Properties
DOI http://dx.doi.org/10.1209/0295-5075/87/47002
Published online 31 August 2009
EPL, 87 (2009) 47002
DOI: 10.1209/0295-5075/87/47002

Violation of Onsager symmetry for a ballistic channel Coulomb coupled to a quantum ring

B. Szafran1, M. R. Poniedziałek1 and F. M. Peeters2

1   Faculty of Physics and Applied Computer Science, AGH University of Science and Technology al. Mickiewicza 30, 30-059 Kraków, Poland, EU
2   Departement Fysica, Universiteit Antwerpen - Groenenborgerlaan 171, B-2020 Antwerpen, Belgium, EU

bszafran@agh.edu.pl

received 18 May 2009; accepted in final form 29 July 2009; published August 2009
published online 31 August 2009

Abstract
We investigate a scattering of electron which is injected individually into an empty ballistic channel containing a cavity that is Coulomb coupled to a quantum ring charged with a single electron. We solve the time-dependent Schrödinger equation for the electron pair with an exact account for the electron-electron correlation. Absorption of energy and angular momentum by the quantum ring is not an even function of the external magnetic field. As a consequence we find that the electron backscattering probability is asymmetric in the magnetic field and thus violates Onsager symmetry.

PACS
73.63.-b - Electronic transport in nanoscale materials and structures.
73.63.Nm - Quantum wires.
73.63.Kv - Quantum dots.

© EPLA 2009