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arXiv · 1301.7021

Extracting quantum work statistics and fluctuation theorems by single qubit interferometry

R. Dorner·S. R. Clark·L. Heaney·R. Fazio·J. Goold·V. Vedral
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Abstract

We propose an experimental scheme to verify the quantum non-equilibrium fluctuation relations using current technology. Specifically, we show that the characteristic function of the work distribution for a non-equilibrium quench of a general quantum system can be extracted from Ramsey interferometry of a single probe qubit. Our scheme paves the way for the full characterisation of non-equilibrium processes in a variety of complex quantum systems ranging from single particles to many-body atomic systems and spin chains. We demonstrate our idea using a time-dependent quench of the motional state of a trapped ion, where the internal pseudo-spin provides a convenient probe qubit.

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R. Dorner, S. R. Clark, L. Heaney, R. Fazio, J. Goold, V. Vedral. 2013-02-11. Extracting quantum work statistics and fluctuation theorems by single qubit interferometry. https://doi.org/10.1103/physrevlett.110.230601

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