The Berry-Foucault Pendulum

TL;DR

This paper demonstrates that a 2D harmonic oscillator with Berry curvature-induced anomalous Hall effect mimics the Foucault pendulum's rotation, enabling precise measurement of Berry curvature through a rotating oscillation plane.

Contribution

It establishes a novel analogy between the Foucault pendulum and a 2D harmonic oscillator with Berry curvature, enhancing AHE observation and measurement techniques.

Findings

The oscillator's plane rotation matches Foucault pendulum behavior.

Rotating configuration improves Berry curvature detection.

Optimal conditions for observing maximal rotation angle are identified.

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.