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arXiv · 1803.03140

Spin excitations and thermodynamics of the t-J model on the 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 t-J Heisenberg model on the honeycomb lattice. Employing a generalized mean-field approximation for arbitrary temperatures and hole dopings, the electronic spectrum of excitations, the spin-excitation spectrum and thermodynamic quantities (two-spin correlation functions, staggered magnetization, magnetic susceptibility, correlation length) are calculated by solving a coupled system of self-consistency equations for the correlation functions. The temperature and doping dependence of the magnetic (uniform static) susceptibility is ascribed to antiferromagnetic short-range order. Our results on the doping dependencies of the magnetization and susceptibility are analyzed in comparison with previous results for the t_J model on the square lattice.

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A. A. Vladimirov, D. Ihle, N. M. Plakida. 2018-03-07. Spin excitations and thermodynamics of the t-J model on the honeycomb lattice. https://doi.org/10.1140/epjb%2Fe2018-80712-x

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