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arXiv · 2008.07933

Experiment-friendly formulation of quantum backflow

Marek Miller·Woo Chee Yuan·Rainer Dumke·Tomasz Paterek
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Abstract

Quantum backflow is usually understood as a quantum interference phenomenon where probability current of a quantum particle points in the opposite direction to particle's momentum. Here, we quantify the amount of quantum backflow for arbitrary momentum distributions, paving the way towards its experimental verification. We give examples of backflow in gravitational and harmonic potential, and discuss experimental procedures required for the demonstration using atomic gravimeters. Such an experiment would show that the probability of finding a free falling particle above initial level could grow for suitably prepared quantum state with most momentum downwards.

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Marek Miller, Woo Chee Yuan, Rainer Dumke, Tomasz Paterek. 2020-08-18. Experiment-friendly formulation of quantum backflow. https://doi.org/10.22331/q-2021-01-11-379

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