Ultrasensitive Magnetometer based on Cusp Points of the Photon-Magnon Synchronization Mode

TL;DR

This paper introduces a highly sensitive magnetometer utilizing photon-magnon synchronization modes, achieving enhanced gyromagnetic ratios and reduced linewidth, promising superior detection of weak magnetic fields for scientific and technological applications.

Contribution

The work demonstrates a novel magnetometer based on cusp points of photon-magnon modes with significantly increased gyromagnetic ratios and ultra-narrow linewidths, surpassing traditional spin resonance-based sensors.

Findings

Gyromagnetic ratio enhanced to 37 times the electron's

Further amplification to 236 times using higher-order modes

Emission linewidth reduced to 0.06 Hz

Abstract

Ultrasensitive magnetometers based on spin resonances have led to remarkable achievements. However, the gyromagnetic ratios of these spin resonances that determine the responsivity of magnetometers to weak magnetic fields are inherently constrained by the Land$\acute{e}$ g-factor of particles, such as the electron, with a constant gyromagnetic ratio of $\gamma_e=2\pi\times28$ GHz/T. Here, we demonstrate an ultrasensitive magnetometer based on the cusp point (CP) of photon-magnon synchronization modes (PMSMs). The PMSM's gyromagnetic ratio at the CP is enhanced to $37\gamma_e$ and further amplified to $236\gamma_e$ by utilizing the sixth-order oscillating mode of the PMSM. Moreover, the emission linewidth of the PMSM can be reduced to 0.06 Hz, resulting in excellent sensitivity to weak magnetic fields. These outstanding properties position our magnetometer to potentially achieve superior sensitivity to conventional magnetometers. Our work introduces a cost-effective prototype for the next generation of magnetometry, and may advance scientific research and technologies that rely on ultrasensitive magnetic field detection.