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arXiv · 0803.3709

Nonadiabatic coherent evolution of two-level systems under spontaneous decay

F. O. Prado·E. I. Duzzioni·M. H. Y. Moussa·N. G. de Almeida·C. J. Villas-Boas
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Abstract

In this paper we extend current perspectives in engineering reservoirs by producing a time-dependent master equation leading to a nonstationary superposition equilibrium state that can be nonadiabatically controlled by the system-reservoir parameters. Working with an ion trapped inside a nonindeal cavity we first engineer effective Hamiltonians that couple the electronic states of the ion with the cavity mode. Subsequently, two classes of decoherence-free evolution of the superposition of the ground and decaying excited levels are achieved: those with time-dependent azimuthal or polar angle. As an application, we generalise the purpose of an earlier study [Phys. Rev. Lett. 96, 150403 (2006)], showing how to observe the geometric phases acquired by the protected nonstationary states even under a nonadiabatic evolution.

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F. O. Prado, E. I. Duzzioni, M. H. Y. Moussa, N. G. de Almeida, C. J. Villas-Boas. 2008-03-26. Nonadiabatic coherent evolution of two-level systems under spontaneous decay. https://doi.org/10.1103/physrevlett.102.073008

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