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arXiv · 2307.03545

Finite-temperature properties of the easy-axis Heisenberg model on frustrated lattices

Martin Ulaga·Jure Kokalj·Alexander Wietek·Andrej Zorko·Peter Prelovšek
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Abstract

Motivated by recent experiments on a compound {displaying Ising-like short-range correlations on the triangular lattice, we study the anisotropic easy-axis spin-$1/2$ Heisenberg model on the triangular and kagome lattice} by performing numerical calculations of finite-temperature properties, in particular of static spin structure factor and of thermodynamic quantities, on systems with up to 36 sites. On the triangular lattice, the low-temperature spin structure factor {exhibits long-range} spin correlations in the whole range of anisotropies, whereas thermodynamic quantities reveal a crossover upon increasing the anisotropy, most pronounced in the vanishing generalized Wilson ratio in the easy-axis regime. In contrast, on the kagome lattice, the spin structure factor is short-range, and thermodynamic quantities evolve steadily between the easy-axis and the isotropic case, consistent with the interpretation in terms of {a} spin liquid.

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Martin Ulaga, Jure Kokalj, Alexander Wietek, Andrej Zorko, Peter Prelovšek. 2023-07-07. Finite-temperature properties of the easy-axis Heisenberg model on frustrated lattices. https://doi.org/10.1103/physrevb.109.035110

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