PreprintCC BY 4.0arXiv
Topology of Fluctuation Bands in Chiral Active Crystals
Abstract
While band topology is usually associated with the deterministic dynamics of a system, we show that it can instead reside in its fluctuations. Using a reciprocal lattice driven by nonequilibrium chiral active noise, we find that the displacement spectrum---which quantifies displacement fluctuations---admits bands with nonzero Chern numbers despite a Chern-trivial deterministic mechanics. A two-band valley theory captures the emergence of this topology through a Dirac mass inversion, a Haldane-type mechanism, or a quadratic band touching, depending on the relevant transition. Through the bulk--boundary correspondence, we find boundary-localized fluctuation modes that are distinct from the usual propagating mechanical edge states.
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BibTeX
@misc{maire2026topology,
title = {{Topology of Fluctuation Bands in Chiral Active Crystals}},
author = {Raphaël Maire},
howpublished = {arXiv},
year = {2026},
month = oct,
doi = {10.48550/arxiv.2608.26055},
eprint = {2608.26055},
archivePrefix = {arXiv},
url = {https://arxiv.org/abs/2608.26055},
note = {CC BY 4.0},
}
RIS
TY - UNPB
TI - Topology of Fluctuation Bands in Chiral Active Crystals
AU - Raphaël Maire
PY - 2026
DA - 2026/10/04
PB - arXiv
DO - 10.48550/arxiv.2608.26055
UR - https://arxiv.org/abs/2608.26055
AB - While band topology is usually associated with the deterministic dynamics of a system, we show that it can instead reside in its fluctuations. Using a reciprocal lattice driven by nonequilibrium chiral active noise, we find that the displacement spectrum---which quantifies displacement fluctuations---admits bands with nonzero Chern numbers despite a Chern-trivial deterministic mechanics. A two-band valley theory captures the emergence of this topology through a Dirac mass inversion, a Haldane-type mechanism, or a quadratic band touching, depending on the relevant transition. Through the bulk--boundary correspondence, we find boundary-localized fluctuation modes that are distinct from the usual propagating mechanical edge states.
ER -