Tunable Magnon-Photon Coupling by Magnon Band Gap in a Layered Hybrid Perovskite Antiferromagnet

TL;DR

This paper demonstrates tunable magnon-photon coupling in a layered hybrid perovskite antiferromagnet by exploiting its magnon band gap, enabling control over hybridization for quantum information applications.

Contribution

It introduces a method to switch off magnon-photon hybridization using the magnon band gap in a layered perovskite antiferromagnet, which is sensitive to temperature.

Findings

Magnon band gap can be controlled via temperature.

Photon mode within the magnon band gap disables hybridization.

Resonator damping rate increases when mode falls into the magnon band gap.

Abstract

Tunability of coherent coupling between fundamental excitations is an important prerequisite for expanding their functionality in hybrid quantum systems. In hybrid magnonics, the dipolar interaction between magnon and photon usually persists and cannot be switched off. Here, we demonstrate this capability by coupling a superconducting resonator to a layered hybrid perovskite antiferromagnet, which exhibits a magnon band gap due to its intrinsic Dzyaloshinskii-Moriya interaction. The pronounced temperature sensitivity of the magnon band gap location allows us to set the photon mode within the gap and to disable magnon-photon hybridization. When the resonator mode falls into the magnon band gap, the resonator damping rate increases due to the nonzero coupling to the detuned magnon mode. This phenomena can be used to quantify the magnon band gap using an analytical model. Our work brings new opportunities in controlling coherent information processing with quantum properties in complex magnetic materials.