Power Dependent Resonant Frequency of a Microwave Cavity due to Magnetic Levitation

TL;DR

This paper investigates how the resonant frequency of a microwave cavity shifts with power levels when a magnet is levitated inside, revealing interactions between the magnet and the cavity's RF field.

Contribution

It presents the first measurements of power-dependent frequency shifts caused by a Meissner-levitated magnet within a microwave cavity, linking levitation dynamics to cavity resonance.

Findings

Resonant frequency shifts with input power and temperature.

The frequency change is attributed to magnet-cavity RF interactions.

Quality factor variations were also observed.

Abstract

Levitation of a magnet by superconductor has been an active area of research to explore the quantum mechanical phenomenon. One of the techniques used is to measure the levitation of a magnet placed inside the superconducting microwave cavity. The levitation height can be probed by measuring the change in microwave frequency. Here, we report measurements of the change in resonance frequency of the microwave cavity with the Meissner-levitated permanent magnet. The change in resonant frequency and quality factor was measured as a function of input power and temperature. The change in resonate frequency is likely due to the interaction of the magnet with the radio-frequency field inside the microwave cavity.