Table of Contents
Physics Research International
Volume 2015, Article ID 706527, 7 pages
http://dx.doi.org/10.1155/2015/706527
Research Article

Comparing the Ratchet Effects of Cold Atoms in Periodically Symmetric and Asymmetric Optical Potentials

1Physics Department, University of Buea, 63 Buea, Cameroon
2African Institute for Mathematical Science (AIMS), 608 Limbe, Cameroon
3Physikalische und Theoretische Chemie, Institut fur Chemie und Biochemie, Freie Universit at Berlin, Takustraße 3, 14195 Berlin, Germany

Received 29 May 2014; Accepted 23 December 2014

Academic Editor: Ali Hussain Reshak

Copyright © 2015 Nkongho Ayuketang Arreyndip and Kenfack Anatole. This is an open access article distributed under the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited.

Abstract

We consider a particle in a spatial symmetric/asymmetric potential driven by time periodic bichromatic AC fields of ratchet type. The associated time-dependent Schrödinger equation is conveniently tackled with the Floquet theory. We next proceed to investigate the ratchet effect induced by the driver, comparing the symmetric with the asymmetric cases. It turns out that the current in the asymmetric case is stronger than that of the symmetric one. Besides, we also investigate the case where the driver is a delta kicked acting on our spatial potential with more emphasis on its chaotic behaviour. Here we check that the current emerges as the phase space is mixed and that the system with asymmetric spatial potential becomes more chaotic than the symmetric one at low kicking strength.