Winding charge density wave: intertwining of structural chirality and phase topology of electronic order

Shun Asano; Youichi Yanase

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arXiv · 2607.03102

Winding charge density wave: intertwining of structural chirality and phase topology of electronic order

Shun Asano·Youichi Yanase

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Abstract

We propose a class of chiral charge density waves (CDWs), dubbed winding CDWs, that exhibit macroscopic chirality despite a single ordering wavevector. In screw-symmetric chiral crystals, chiral phonons drive a Peierls instability that selects a definite crystal angular momentum channel, thereby endowing the CDW with an integer azimuthal phase winding dictated by the selection rule governing electron-phonon coupling. We further extend this framework to achiral crystals with discrete rotational symmetry and demonstrate that spontaneous symmetry breaking stabilizes a winding CDW with either handedness, realizing an achiral-to-chiral phase transition. Our results reveal a fundamental link between the geometry of chiral structures and the phase topology of electronic orders.

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Shun Asano, Youichi Yanase. 2026-07-03. Winding charge density wave: intertwining of structural chirality and phase topology of electronic order. https://arxiv.org/abs/2607.03102

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