Crossover Phase Diagram of 2D Heisenberg Ferro- and Antiferromagnets

Alexander Sokol; Norbert Elstner; Rajiv R. P. Singh

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arXiv · cond-mat/9505148

Crossover Phase Diagram of 2D Heisenberg Ferro- and Antiferromagnets

Alexander Sokol·Norbert Elstner·Rajiv R. P. Singh

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Abstract

We propose a single crossover phase diagram applicable to 2D collinear Heisenberg antiferromagnets (AFMs) and ferromagnets (FMs), and show that the scaling regimes of AFMs and FMs are in one-to-one correspondence. The phase diagram is split into classical and quantum regions. Our two key results are: (i) in the classical region, the AFMs and FMs exhibit nearly identical behavior near their respective ordering wavevectors, which we observe for S=1 and higher using series expansions; and (ii) in the quantum region, quantum critical (QC) regime is present not only for the AFMs, but for FMs as well.

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Alexander Sokol, Norbert Elstner, Rajiv R. P. Singh. 1995-05-30. Crossover Phase Diagram of 2D Heisenberg Ferro- and Antiferromagnets. https://arxiv.org/abs/cond-mat/9505148

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