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arXiv · 1103.5124

Quantum Heisenberg antiferromagnet on low-dimensional frustrated lattices

Oleg Derzhko·Taras Krokhmalskii·Johannes Richter
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Abstract

Using a lattice-gas description of the low-energy degrees of freedom of the quantum Heisenberg antiferromagnet on the frustrated two-leg ladder and bilayer lattices we examine the magnetization process at low temperatures for these spin models. In both cases the emergent discrete degrees of freedom implicate a close relation of the frustrated quantum Heisenberg antiferromagnet to the classical lattice gas with finite nearest-neighbor repulsion or, equivalently, to the Ising antiferromagnet in a uniform magnetic field. Using this relation we obtain analytical results for thermodynamically large systems in the one-dimensional case. In the two-dimensional case we perform classical Monte Carlo simulations for systems of up to $100 \times 100$ sites.

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Oleg Derzhko, Taras Krokhmalskii, Johannes Richter. 2011-03-26. Quantum Heisenberg antiferromagnet on low-dimensional frustrated lattices. https://doi.org/10.1007/s11232-011-0101-3

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