Dynamic Modulation of Long Range Photon Magnon Coupling

TL;DR

This paper presents experimental evidence of long-range, tunable dissipative magnon-photon coupling mediated by auxiliary modes, demonstrating non-Hermitian dynamics and level attraction in a controllable cavity magnonic system.

Contribution

It introduces a novel method for in situ tuning of dissipative coupling in long-range magnon-photon systems using an auxiliary mode, enabling exploration of non-Hermitian physics.

Findings

Observation of level attraction in frequency domain

Time-domain signatures of dissipative coupling

In situ tunability of coupling strength

Abstract

Evidence of non-hermitian behavior has been recently demonstrated in cavity magnonics, including the emergence of mode level attraction and exceptional points in spectroscopic measurements. This work demonstrates experimental evidence of time-domain dynamics of magnon-photon systems that are coupled through a long-range interaction (i.e. remote coupling) exhibiting level attraction mediated by an auxiliary mode. We directly observe the temporal evolution of dissipatively coupled cavity-magnon modes, where heavily damped transmission line modes mediate the interaction. Our frequency-domain measurements confirm the predicted level attraction, while time-domain ring-down measurements reveal the characteristic signatures of dissipative coupling dynamics. Our approach offers in situ tunability over the dissipative coupling strength, including complete suppression, without requiring physical modifications to the experimental setup, providing a versatile platform for exploring tunable, non-Hermitian physics.