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arXiv · 2212.11003

The Berry-Foucault Pendulum

D. D. Solnyshkov·I. Septembre·K. Ndiaye·G. Malpuech
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Abstract

The geometric phase is known to play a role both in the rotation of the Foucault pendulum and in the anomalous Hall effect (AHE) due to the Berry curvature. Here, we show that a 2D harmonic oscillator with AHE induced by Berry curvature behaves exactly like the Foucault pendulum: in both, the plane of the oscillations rotates with time. The rotating pendulum configuration enhances the AHE, simplifying its observation and allowing high-precision measurements of the Berry curvature. We also show how the non-adiabaticity and anharmonicity determine the maximal rotation angle and find the optimal conditions for the observations.

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D. D. Solnyshkov, I. Septembre, K. Ndiaye, G. Malpuech. 2022-12-21. The Berry-Foucault Pendulum. https://arxiv.org/abs/2212.11003

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