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arXiv · 2302.01773

Absence of fractal quantum criticality in the quantum Newman-Moore model

R. Wiedmann·L. Lenke.·M. Mühlhauser·K. P. Schmidt
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Abstract

The quantum phase transition between the low-field fracton phase with type-II fracton excitations and the high-field polarized phase is investigated in the two-dimensional self-dual quantum Newman-Moore model. We apply perturbative and numerical linked-cluster expansions to calculate the ground-state energy per site in the thermodynamic limit revealing a level crossing at the self-dual point. In addition, high-order series expansions of the relevant low-energy gaps are determined using perturbative continuous unitary transformations indicating no gap-closing. Our results therefore predict a first-order phase transition between the low-field fracton and the high-field polarized phase at the self-dual point.

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R. Wiedmann, L. Lenke., M. Mühlhauser, K. P. Schmidt. 2023-02-03. Absence of fractal quantum criticality in the quantum Newman-Moore model. https://arxiv.org/abs/2302.01773

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