# Elementary excitation in the spin-stripe phase in quantum chains

## TL;DR

This paper reports the discovery of a new elementary excitation called 'wigglon' in a spin-stripe phase of a quantum magnetic chain, revealing complex bound states of quasiparticles and enriching understanding of stripe physics in correlated electron systems.

## Contribution

It introduces the 'wigglon', a novel bound state of phason quasiparticles, observed in a frustrated zigzag spin chain, expanding the understanding of excitations in spin-stripe phases.

## Key findings

- Observation of 'wigglons' in $eta$-TeVO$_4$
- Unusual low-frequency spin dynamics in the spin-stripe phase
- Insight into stripe physics of strongly-correlated systems

## Abstract

Elementary excitations in condensed matter capture the complex many-body dynamics of interacting basic entities in a simple quasiparticle picture. In magnetic systems the most established quasiparticles are magnons, collective excitations that reside in ordered spin structures, and spinons, their fractional counterparts that emerge in disordered, yet correlated spin states. Here we report on the discovery of elementary excitation inherent to spin-stripe order that represents a bound state of two phason quasiparticles, resulting in a wiggling-like motion of the magnetic moments. We observe these excitations, which we dub "wigglons", in the frustrated zigzag spin-1/2 chain compound $\beta$-TeVO$_4$, where they give rise to unusual low-frequency spin dynamics in the spin-stripe phase. This result provides insights into the stripe physics of strongly-correlated electron systems.