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arXiv · 2406.11952

Solitons with irrational charge in a one-dimensional quantum ferroelectric

Sijia Zhao·Steven A. Kivelson
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Abstract

We use analytic (mean-field) and density-matrix renormalization group (DMRG) methods to study a simplified one-dimensional version of the SSH-Holstein model of electron-phonon interactions with one electron per site (half filling) where, as a function of the ratio of the two couplings, three distinct insulating phases arise - a site-centered charge-density-wave (CDW), a bond-centered bond-density-wave (BDW), and an intermediate ferroelectric (inversion-symmetry breaking) phase with coexisting CDW and BDW order. In the intermediate phase our DMRG results establish the existence of point-like soliton excitations with irrational charge (that depends on a ratio of coupling constants) and either spin 1/2 or spin 0, and a surprisingly light effective mass.

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Sijia Zhao, Steven A. Kivelson. 2024-06-17. Solitons with irrational charge in a one-dimensional quantum ferroelectric. https://arxiv.org/abs/2406.11952

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