# Collective spin excitations of helices and magnetic skyrmions: review and perspectives of magnonics in non-centrosymmetric magnets

## TL;DR

This review discusses how complex spin structures like helices and skyrmions in non-centrosymmetric magnets enhance microwave properties, highlighting their potential for low-energy magnonic applications in electronics.

## Contribution

It provides a comprehensive overview of collective spin excitations in complex magnetic structures and explores their implications for future magnonic technologies.

## Key findings

- Skyrmion lattices influence microwave characteristics of magnetic materials.
- Insulating non-centrosymmetric magnets offer low damping and electric field control.
- Potential for energy-efficient magnonic devices is highlighted.

## Abstract

Magnetic materials hosting correlated electrons play an important role for information technology and signal processing. The currently used ferro-, ferri- and antiferromagnetic materials provide microscopic moments (spins) that are mainly collinear. Recently more complex spin structures such as spin helices and cycloids have regained a lot of interest. The interest has been initiated by the discovery of the skyrmion lattice phase in non-centrosymmetric helical magnets. In this review we address how spin helices and skyrmion lattices enrich the microwave characteristics of magnetic materials. When discussing perspectives for microwave electronics and magnonics we focus particularly on insulating materials as they avoid eddy current losses, offer low spin-wave damping, and might allow for electric field control of collective spin excitations. Thereby, they further fuel the vision of magnonics operated at low energy consumption.