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arXiv · 2411.08331

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

Dirk Wulferding·Jongho Park·Takami Tohyama·Seung Ryong Park·Changyoung Kim
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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.

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Dirk Wulferding, Jongho Park, Takami Tohyama, Seung Ryong Park, Changyoung Kim. 2024-11-13. Magnetic field control over the axialness of Higgs modes in charge-density wave compounds. https://doi.org/10.1038/s41467-024-55355-y

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