Europhys. Lett.
Volume 72, Number 1, October 2005
Page(s) 21 - 27
Section General
Published online 31 August 2005
Europhys. Lett., 72 (1), pp. 21-27 (2005)
DOI: 10.1209/epl/i2005-10209-9

Nonadiabatic geometric phase induced by a counterpart of the Stark shift

E. I. Duzzioni1, C. J. Villas-Bôas1, S. S. Mizrahi1, M. H. Y. Moussa1 and R. M. Serra1, 2

1  Departamento de Física, Universidade Federal de São Carlos P.O. Box 676, São Carlos, 13565-905, São Paulo, Brazil
2  Optics Section, The Blackett Laboratory, Imperial College - London SW7 2BZ, UK

received 20 January 2005; accepted in final form 4 August 2005
published online 31 August 2005

We analyse the geometric phase due to the Stark shift in a system composed of a bosonic field, driven by time-dependent linear amplification, interacting dispersively with a two-level (fermionic) system. We show that a geometric phase factor in the joint state of the system, which depends on the fermionic state (resulting form the Stark shift), is introduced by the amplification process. A clear geometrical interpretation of this phenomenon is provided. We also show how to measure this effect in an interferometric experiment and to generate geometric "Schrödinger cat"-like states. Finally, considering the currently available technology, we discuss a feasible scheme to control and measure such geometric phases in the context of cavity quantum electrodynamics.

03.65.Vf - Phases: geometric; dynamic or topological.
42.50.Ct - Quantum description of interaction of light and matter; related experiments.
42.50.Pq - Cavity quantum electrodynamics; micromasers.

© EDP Sciences 2005