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arXiv · 1703.08391

Spin excitations and thermodynamics of the antiferromagnetic Heisenberg model on the layered honeycomb lattice

A. A. Vladimirov·D. Ihle·N. M. Plakida
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Abstract

We present a spin-rotation-invariant Green-function theory for the dynamic spin susceptibility in the spin-1/2 antiferromagnetic Heisenberg model on a stacked honeycomb lattice. Employing a generalized mean-field approximation for arbitrary temperatures, the thermodynamic quantities (two-spin correlation functions, internal energy, magnetic susceptibility, staggered magnetization, N'eel temperature, correlation length) and the spin-excitation spectrum are calculated by solving a coupled system of self-consistency equations for the correlation functions. The temperature dependence of the magnetic (uniform static) susceptibility is ascribed to antiferromagnetic short-range order. The Néel temperature is calculated for arbitrary interlayer couplings. Our results are in a good agreement with numerical computations for finite clusters and with available experimental data on the β-Cu2V2O2 compound.

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A. A. Vladimirov, D. Ihle, N. M. Plakida. 2017-03-24. Spin excitations and thermodynamics of the antiferromagnetic Heisenberg model on the layered honeycomb lattice. https://doi.org/10.1140/epjb%2Fe2017-70720-9

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