# High-efficiency triple-resonant inelastic light scattering in planar optomagnonic cavities

## TL;DR

This paper presents a novel planar optomagnonic cavity design that achieves high triple-resonant inelastic light scattering efficiency, enabling effective microwave-to-optical photon conversion for quantum technologies.

## Contribution

The authors introduce a new time Floquet scattering-matrix approach to optimize a multilayer planar cavity with Ce:YIG, achieving significantly higher conversion efficiencies than previous designs.

## Key findings

- Achieves about 5% conversion efficiency in realistic conditions.
- Demonstrates orders of magnitude improvement over alternative designs.
- Provides a platform for quantum information inter-conversion and fundamental studies.

## Abstract

Optomagnonic cavities have recently been emerging as promising candidates for implementing coherent microwave-to-optical conversion, quantum memories and devices, and next generation quantum networks. A key challenge in the design of such cavities is the attainment of high efficiencies, which could, e.g., be exploited for efficient optical interfacing of superconducting qubits, as well as the practicality of the final designs, which ideally should be planar and amenable to on-chip integration. Here, on the basis of a novel time Floquet scattering-matrix approach, we report on the design and optimization of a planar, multilayer optomagnonic cavity, incorporating a Ce:YIG thin film, magnetized in-plane, operating in the triple-resonant inelastic light scattering regime. This architecture allows for conversion efficiencies of about 5%, under realistic conditions, which is orders of magnitude higher than alternative designs. Our results suggest a viable way forward for realizing practical information inter-conversion between microwave photons and optical photons, mediated by magnons, with efficiencies intrinsically greater than those achieved in optomechanics and alternative related technologies, as well as a platform for fundamental studies of classical and quantum dynamics in magnetic solids, and implementation of futuristic quantum devices.