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arXiv · 1707.06952

Geometric phase corrections on a moving particle in front of a dielectric mirror

Fernando C. Lombardo·Paula I. Villar
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Abstract

We consider an atom (represented by a two-level system) moving in front of a dielectric plate, and study how traces of dissipation and decoherence (both effects induced by vacuum field fluctuations) can be found in the corrections to the unitary geometric phase accumulated by the atom. We consider the particle to follow a classical, macroscopically-fixed trajectory and integrate over the vacuum field and the microscopic degrees of freedom of both the plate and the particle in order to calculate friction effects. We compute analytically and numerically the non-unitary geometric phase for the moving qubit under the presence of the quantum vacuum field and the dielectric mirror. We find a velocity dependence in the correction to the unitary geometric phase due to quantum frictional effects. We also show in which cases decoherence effects could, in principle, be controlled in order to perform a measurement of the geometric phase using standard procedures as Ramsey-like interferometry.

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Fernando C. Lombardo, Paula I. Villar. 2017-07-21. Geometric phase corrections on a moving particle in front of a dielectric mirror. https://doi.org/10.1209/0295-5075/118/50003

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