# Hybrid quantum systems based on magnonics

## TL;DR

This review discusses hybrid quantum systems utilizing magnonic excitations in ferromagnetic materials, highlighting their interactions with various quantum platforms and potential applications in quantum information and sensing.

## Contribution

It provides a comprehensive overview of experimental platforms and the coherent interactions in magnon-based hybrid quantum systems, emphasizing their role in advancing quantum technologies.

## Key findings

- Magnons can coherently interact with microwave, optical, and mechanical systems.
- Hybrid systems based on magnonics enable quantum information processing.
- Potential for quantum sensing applications using magnonic platforms.

## Abstract

Engineered quantum systems enabling novel capabilities for communication, computation, and sensing have blossomed in the last decade. Architectures benefiting from combining distinct and complementary physical quantum systems have emerged as promising platforms for developing quantum technologies. A new class of hybrid quantum systems based on collective spin excitations in ferromagnetic materials has led to the diverse set of experimental platforms which are outlined in this review article. The coherent interaction between microwave cavity modes and collective spin-wave modes is presented as the backbone of the development of more complex hybrid quantum systems. Indeed, quanta of excitation of the spin-wave modes, called magnons, can also interact coherently with optical photons, phonons, and superconducting qubits in the fields of cavity optomagnonics, cavity magnomechanics, and quantum magnonics, respectively. Notably, quantum magnonics provides a promising platform for performing quantum optics experiments in magnetically-ordered solid-state systems. Applications of hybrid quantum systems based on magnonics for quantum information processing and quantum sensing are also outlined briefly.