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arXiv · 2501.07632

Magnetic field fluctuations induced decoherence of a diamagnetic nanosphere

Ruiyun Zhang·Martine Schut·Anupam Mazumdar
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Abstract

This paper provides a simple derivation of the decoherence rate for a diamagnetic nanoparticle in the presence of fluctuations of the magnetic field in a thermal environment. Diamagnetic levitation is one of the key techniques for trapping, cooling, and creating a macroscopic quantum spatial superposition in many experiments. It is widely applied in many theoretical and experimental endeavours to test fundamental physics in matter-wave interferometers. To estimate the decoherence rate originating from magnetic-field fluctuations, we use the fluctuation-dissipation theorem. We show that our resulting decoherence rate expression is analogous to that of a dielectric material interacting with the electric field component of the background field; however, it is often relatively suppressed due to the material properties.

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Ruiyun Zhang, Martine Schut, Anupam Mazumdar. 2025-01-13. Magnetic field fluctuations induced decoherence of a diamagnetic nanosphere. https://doi.org/10.1088/1402-4896%2Fae0986

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