Magnetic field control over the axialness of Higgs modes in charge-density wave compounds

TL;DR

This study demonstrates magnetic field tuning of axial Higgs modes in charge-density wave compounds, revealing their direct relation to magnetic degrees of freedom and enabling in-situ control of their axialness.

Contribution

It introduces a method to control the axial character of Higgs modes using magnetic fields in charge-density wave materials, a novel approach in the field.

Findings

Proportionality between axial Higgs component and magnetic field.

90° phase shift when changing magnetic field direction.

Magnetic degrees of freedom influence Higgs mode axialness.

Abstract

Understanding how symmetry-breaking processes generate order out of disorder is among the most fundamental problems of nature. The scalar Higgs mode - a massive (quasi-) particle - is a key ingredient in these processes and emerges with the spontaneous breaking of a continuous symmetry. Its related exotic and elusive axial counterpart, a Boson with vector character, can be stabilized through the simultaneous breaking of multiple continuous symmetries. Here, we employ a magnetic field to tune the recently discovered axial Higgs-type charge-density wave amplitude modes in rare-earth tritellurides. We demonstrate a proportionality between the axial Higgs component and the applied field, and a 90$^{\circ}$ phase shift upon changing the direction of the B-field. This indicates that the axial character is directly related to magnetic degrees of freedom. Our approach opens up an in-situ control over the axialness of emergent Higgs modes.