An N-loop potential energy model for levitated mm-scale magnets in cm-scale superconducting coaxial microwave resonators

Jeffrey Miller; Nabin K. Raut; Demitrius Zulevic; Harold Hart; Luis A. Martinez; Alessandro Castelli; Raymond Chiao; Jay E. Sharping

arXiv · 2306.08662

An N-loop potential energy model for levitated mm-scale magnets in cm-scale superconducting coaxial microwave resonators

Jeffrey Miller·Nabin K. Raut·Demitrius Zulevic·Harold Hart·Luis A. Martinez·Alessandro Castelli·Raymond Chiao·Jay E. Sharping

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Abstract

The levitation of a macroscopic object within a superconducting resonator provides a unique and novel platform to study optomechanics, quantum information, and gravitational wave detection. Existing mirror-method and single-loop models for calculating magnet levitation are insufficient for predicting the position and motion of the levitated magnet. If the cavity-magnet interaction is modeled using a large number of smaller surface current loops, one can quantitatively model the dynamics of the levitation of the magnet within the cavity. The magnet's most-likely position and orientation can be predicted for non-trivial cavity geometries and cavity orientations. Knowing the potential energy landscape within the cavity configuration also provides a means to estimate the resonant mechanical frequencies at which the levitated magnet vibrates, and enables tailoring the cavity design for specific outcomes.

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Jeffrey Miller, Nabin K. Raut, Demitrius Zulevic, Harold Hart, Luis A. Martinez, Alessandro Castelli, Raymond Chiao, Jay E. Sharping. 2023-06-14. An N-loop potential energy model for levitated mm-scale magnets in cm-scale superconducting coaxial microwave resonators. https://arxiv.org/abs/2306.08662

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