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arXiv · 1905.05218

Competing Orders and Unconventional Criticality in the Su-Schrieffer-Heeger Model

Manuel Weber·Francesco Parisen Toldin·Martin Hohenadler
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Abstract

The phase diagram of the one-dimensional Su-Schrieffer-Heeger model of spinless fermions coupled to quantum phonons is determined by quantum Monte Carlo simulations. It differs significantly from previous work. In addition to Luttinger liquid and bond-order-wave (BOW) phases, we find an extended charge-density-wave (CDW) phase. Because of different broken symmetries, BOW and CDW phases are connected by a retardation-driven phase transition. Our results are consistent with the theory of the frustrated $XXZ$ chain, including unconventional power-law exponents at criticality, and an interpretation in terms of deconfined quantum criticality via proliferation of solitons.

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Manuel Weber, Francesco Parisen Toldin, Martin Hohenadler. 2019-05-13. Competing Orders and Unconventional Criticality in the Su-Schrieffer-Heeger Model. https://doi.org/10.1103/physrevresearch.2.023013

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