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arXiv · 1908.07058

Topological order in matrix Ising models

Sean A. Hartnoll·Edward A. Mazenc·Zhengyan D. Shi
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Abstract

We study a family of models for an $N_1 \times N_2$ matrix worth of Ising spins $S_{aB}$. In the large $N_i$ limit we show that the spins soften, so that the partition function is described by a bosonic matrix integral with a single `spherical' constraint. In this way we generalize the results of [1] to a wide class of Ising Hamiltonians with $O(N_1,\mathbb{Z})\times O(N_2,\mathbb{Z})$ symmetry. The models can undergo topological large $N$ phase transitions in which the thermal expectation value of the distribution of singular values of the matrix $S_{aB}$ becomes disconnected. This topological transition competes with low temperature glassy and magnetically ordered phases.

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Sean A. Hartnoll, Edward A. Mazenc, Zhengyan D. Shi. 2019-08-19. Topological order in matrix Ising models. https://doi.org/10.21468/scipostphys.7.6.081

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