Topological Berry phase of a pumped three-level atom in the presence of dispersing and absorbing dielectric bodies: application to a half-space dielectric surface

M. S. Ateto

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arXiv · 1109.0339

Topological Berry phase of a pumped three-level atom in the presence of dispersing and absorbing dielectric bodies: application to a half-space dielectric surface

M. S. Ateto

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Abstract

Within the framework of exact quantum electrodynamics in dielectric, we study the topological Berry phase of a classically pumped $\Lambda$-type three-level atom, prepared initially in a superposition of its two pumped levels and located near a planar dielectric half-space with model permittivity of Lorentz type, interacts with a vacuum field. The effects of material losses, expressed in terms of the Green tensor of the dielectric-matter formation including dispersion and absorption, on the topological Berry phase of the photon transition between the pumped levels have been studied. The outcomes are compared with that of an atom in free space. We expect, the additional noise due to presence of the dielectric will modify, in a unified way, the behavior and values measured of the phase shift between the wavefunction evolution and its original state. It is shown that for small separation distance between atom and the dielectric surface, the angle separation between the wavefunction evolution and the original state reduced noticeably that is of strong applications in construction of the universal quantum logic gates. Further, the study opens routes for new challenging applications of atomically systems as various sources of coherent light emitted by pumped atoms in dielectric surroundings.

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M. S. Ateto. 2011-09-02. Topological Berry phase of a pumped three-level atom in the presence of dispersing and absorbing dielectric bodies: application to a half-space dielectric surface. https://arxiv.org/abs/1109.0339

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