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arXiv · 1609.06837

High-temperature expansion for frustrated magnets: Application to the J1-J2 model on the BCC lattice

Johannes Richter·Patrick Müller·Andre Lohmann·Heinz-Jürgen Schmidt
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Abstract

We present the high-temperature expansion up to 11th order for the specific heat $C$ and the uniform susceptibility $χ_0$ and up to 9th order for the structure factor $S_{\bf Q}$ of the frustrated spin-half $J_1$-$J_2$ Heisenberg model on the BCC lattice. We consider ferromagnetic as well as antiferromagnetic nearest-neighbor exchange $J_1$ and frustrating antiferromagnetic next-nearest-neighbor exchange $J_2$. We discuss the influence of frustration on the temperature dependence of these quantities. Furthermore, we use the HTE series to determine the critical temperature $T_c$ as a function of the frustration parameter $J_2$.

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Johannes Richter, Patrick Müller, Andre Lohmann, Heinz-Jürgen Schmidt. 2016-09-22. High-temperature expansion for frustrated magnets: Application to the J1-J2 model on the BCC lattice. https://doi.org/10.1016/j.phpro.2015.12.105

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