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arXiv · 2410.03326

A multicritical point of $S = 1$ XXZ chain with single ion anisotropy

Shuichi Shiraishi·Kiyohide Nomura
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Abstract

We research the ground state of the $S = 1$ XXZ spin chain with single ion anisotropy, focusing on XY1, XY2 (Spin Nematic), Neel, Haldane phases. Recently, it was reported that the four phases did not intersect at a single point using conventional numerical methods, which is inconsistent with the bosonization theory. In order to resolve this discrepancy, we propose a unified method to determine phase boundaries by combining conformal field theory (CFT) with numerical diagonalization. And we discuss the symmetry and universality class of the multicritical point.

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Shuichi Shiraishi, Kiyohide Nomura. 2024-10-04. A multicritical point of $S = 1$ XXZ chain with single ion anisotropy. https://doi.org/10.1103/physrevb.111.024406

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