Coherent Microwave Emission of a Gain-Driven Polariton

TL;DR

This paper introduces a gain-driven polariton platform in cavity magnonics, demonstrating novel light-matter interactions and high-coherence microwave emission through experimental and theoretical analysis.

Contribution

It presents the first experimental realization of gain-driven polaritons with unique auto-oscillations and phase singularities, enabling high-coherence microwave amplification.

Findings

Achieved ~40 dB microwave amplification.

Demonstrated high-quality coherent microwave emission with Q > 10^9.

Observed gain-induced magnon-photon synchronization.

Abstract

By developing a gain-embedded cavity magnonics platform, we create gain-driven polariton (GDP) that is activated by an amplified electromagnetic field. Distinct effects of gain-driven light-matter interaction, such as polariton auto-oscillations, polariton phase singularity, self-selection of a polariton bright mode, and gain-induced magnon-photon synchronization, are theoretically studied and experimentally manifested. Utilizing the gain-sustained photon coherence of the GDP, we demonstrate polariton-based coherent microwave amplication (~ 40 dB) and achieve high-quality coherent microwave emission (Q > 10^9).