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arXiv · 1108.0701

Geometric phase kickback in a mesoscopic qubit-oscillator system

G. Vacanti·R. Fazio·M. S. Kim·G. M. Palma·M. Paternostro·V. Vedral
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Abstract

We illustrate a reverse Von Neumann measurement scheme in which a geometric phase induced on a quantum harmonic oscillator is measured using a microscopic qubit as a probe. We show how such a phase, generated by a cyclic evolution in the phase space of the harmonic oscillator, can be kicked back on the qubit, which plays the role of a quantum interferometer. We also extend our study to finite-temperature dissipative Markovian dynamics and discuss potential implementations in micro and nano-mechanical devices coupled to an effective two-level system.

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G. Vacanti, R. Fazio, M. S. Kim, G. M. Palma, M. Paternostro, V. Vedral. 2011-08-02. Geometric phase kickback in a mesoscopic qubit-oscillator system. https://doi.org/10.1103/physreva.85.022129

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