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arXiv · 2504.12489

Searching for Bloch wave packets with almost definite momentum direction

Arseni Goussev·Gregory V. Morozov
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Abstract

The motion of a quantum particle in a one-dimensional periodic potential can be described in terms of Bloch wave packets. Like free-particle wave packets, they can propagate without attenuation. Here, we examine this similarity more closely by investigating whether Bloch wave packets can maintain a definite -- or nearly definite -- momentum direction, a property inherent to free-particle wave packets. This question is particularly relevant to the feasibility of using solid-state-based systems in the search for the first experimental realization of quantum backflow, a quantum interference effect in which a particle's probability density flows in a direction opposite to its momentum.

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Arseni Goussev, Gregory V. Morozov. 2025-04-16. Searching for Bloch wave packets with almost definite momentum direction. https://doi.org/10.1103/k9km-k3dm

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