A room-temperature cavity-magnonic source of correlated microwave pairs

TL;DR

This paper demonstrates a room-temperature hybrid magnon-photon system that generates correlated microwave photon pairs with strong inter-mode correlations, enabling scalable quantum and classical communication applications.

Contribution

It introduces a novel non-degenerate magnon-photon coupling platform at room temperature, producing correlated microwave pairs with verified randomness and multi-channel correlations.

Findings

Strong correlated microwave signals emitted at room temperature

Non-degenerate magnon-photon excitations achieved through dual cavity modes

Verified true randomness and noise-resilient secure communication

Abstract

Correlated microwave photon sources are key enablers for technologies in quantum-limited sensing, signal amplification and communication, but the reliance on millikelvin operating temperature limits their scalability for broader applications. Here, at room temperature, we demonstrate strong correlated microwave signals emitted from a hybrid magnon-photon platform. Different from traditional parametrically induced magnons with degenerate frequencies, we achieve non-degenerate excitations by coupling magnon modes simultaneously with two cavity photon modes. Through the magnon-photon interactions in the corresponding linear and nonlinear regimes, one input microwave photon splits into a pair of magnon polaritons that possess distinct frequencies but maintain strong inter-mode correlations. The nonlinear magnon polariton dynamics empowered by this new parametric platform brings both verified true randomness and robust multi-channel correlations, from which we construct a microwave communication experiment for noise resilient signal transmission with added security. This work establishes cavity magnonics as a versatile and compact platform for generating correlated multi-mode microwave signals, opening new avenues for applications in classical and quantum domains.