Europhys. Lett.
Volume 69, Number 2, January 2005
Page(s) 277 - 283
Section Condensed matter: electronic structure, electrical, magnetic, and optical properties
Published online 15 December 2004
Europhys. Lett., 69 (2), pp. 277-283 (2005)
DOI: 10.1209/epl/i2004-10342-y

Ultrafast build-up of polarization in mesoscopic rings

A. Matos-Abiague and J. Berakdar

Max-Planck Institut für Mikrostrukturphysik - Weinberg 2, 06120 Halle, Germany

received 14 September 2004; accepted in final form 15 November 2004
published online 15 December 2004

Subjecting a non-interacting mesoscopic ring (MR) to a linearly polarized half-cycle electromagnetic pulse results in a non-uniform, non-equilibrium coherent population of electronic states. A post-pulse charge polarization of the ring is then created within few picoseconds and sustains for times determined by the relaxation time scale. These conclusions are the results of a theoretical analysis of the electronic quantum dynamics of a MR subjected to unipolar pulses. Methods to trace experimentally the charge polarization build-up are suggested.

78.67.-n - Optical properties of low-dimensional, mesoscopic, and nanoscale materials and structures.
73.23.-b - Electronic transport in mesoscopic systems.
73.23.Ad - Ballistic transport.

© EDP Sciences 2005