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Metamagnetism in the XXZ model with next-to-nearest-neighbor coupling

C. Gerhardt·K. -H. Mütter·H. Kröger
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Abstract

We investigate groundstate energies and magnetization curves in the one dimensional XXZ-model with next to nearest neighbour coupling $α>0$ and anisotropy $Δ$ ($-1 \le Δ\le 1$) at T=0. In between the familiar ferro- and antiferromagnetic phase we find a transition region -- called metamagnetic phase -- where the magnetization curve is discontinuous at a critical field $B_c(α,Δ)$.

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C. Gerhardt, K. -H. Mütter, H. Kröger. 1999-02-03. Metamagnetism in the XXZ model with next-to-nearest-neighbor coupling. https://doi.org/10.1103/physrevb.57.11504

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