Issue
EPL
Volume 78, Number 5, June 2007
Article Number 57001
Number of page(s) 6
Section Condensed Matter: Electronic Structure, Electrical, Magnetic and Optical Properties
DOI http://dx.doi.org/10.1209/0295-5075/78/57001
Published online 11 May 2007
EPL, 78 (2007) 57001
DOI: 10.1209/0295-5075/78/57001

Nonequilibrium charge dynamics of light-driven rings threaded by a magnetic flux

A. S. Moskalenko1, 2, A. Matos-Abiague3 and J. Berakdar2

1  Max-Planck-Institut für Mikrostrukturphysik - Weinberg 2, 06120 Halle, Germany
2  Institut für Physik, Martin-Luther-Universität Halle-Wittenberg, Nanotechnikum-Weinberg, Heinrich-Damerow-St. 4, 06120 Halle, Germany
3  Institute for Theoretical Physics,University of Regensburg - 93040 Regensburg, Germany


received 16 January 2007; accepted in final form 13 April 2007; published June 2007
published online 11 May 2007

Abstract
We study theoretically the charge polarization and the charge current dynamics of a mesoscopic ring driven by short asymmetric electromagnetic pulses and threaded by an external static magnetic flux. It is shown that the pulse-induced charge polarization and the associated light emission is controllable by tuning the external magnetic flux. Applying two mutually perpendicular pulses triggers a charge current in the ring. The interplay between this nonequilibrium and the persistent currents is investigated and the conditions under which the pulses stop the persistent current are identified.

PACS
73.23.-b - Electronic transport in mesoscopic systems.
73.23.Ra - Persistent currents.
42.65.Re - Ultrafast processes; optical pulse generation and pulse compression.

© Europhysics Letters Association 2007