Saved in:
Bibliographic Details
Main Author: Ziegler, Klaus
Format: Preprint
Published: 2025
Subjects:
Online Access:https://arxiv.org/abs/2507.08127
Tags: Add Tag
No Tags, Be the first to tag this record!
_version_ 1866912956710649856
author Ziegler, Klaus
author_facet Ziegler, Klaus
contents We investigate the topological consequences of coupling chiral fermions to local, dispersionless phonons. This interaction induces a splitting of the phonon spectrum into three bands: a flat band and two bands with linear dispersion, all of which are degenerate at a nodal point located at zero wavevector. The flat band exhibits vanishing Berry curvature, while the linearly dispersing bands carry nontrivial topological features. Their Berry curvature fields assume a hedgehog-like structure in momentum space, analogous to monopole configurations, and reflect the chirality of the underlying fermionic system. Moreover, the effective phonon response reveals a phonon parity anomaly, observable as a discontinuity in the phonon current. This anomaly originates from the singularities of the fermion Green's function and signals the transfer of topological information from fermions to phonons. Our results demonstrate that phonon currents provide a direct probe of electronic chirality and topological structures.
format Preprint
id arxiv_https___arxiv_org_abs_2507_08127
institution arXiv
publishDate 2025
record_format arxiv
spellingShingle Phonon mode splitting and phonon anomaly in multiband electron systems
Ziegler, Klaus
Mesoscale and Nanoscale Physics
We investigate the topological consequences of coupling chiral fermions to local, dispersionless phonons. This interaction induces a splitting of the phonon spectrum into three bands: a flat band and two bands with linear dispersion, all of which are degenerate at a nodal point located at zero wavevector. The flat band exhibits vanishing Berry curvature, while the linearly dispersing bands carry nontrivial topological features. Their Berry curvature fields assume a hedgehog-like structure in momentum space, analogous to monopole configurations, and reflect the chirality of the underlying fermionic system. Moreover, the effective phonon response reveals a phonon parity anomaly, observable as a discontinuity in the phonon current. This anomaly originates from the singularities of the fermion Green's function and signals the transfer of topological information from fermions to phonons. Our results demonstrate that phonon currents provide a direct probe of electronic chirality and topological structures.
title Phonon mode splitting and phonon anomaly in multiband electron systems
topic Mesoscale and Nanoscale Physics
url https://arxiv.org/abs/2507.08127