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Anomalous magnetization process in frustrated spin ladders

Tôru Sakai·Kiyomi Okamoto·Kouichi Okunishi·Masahiro Sato
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Abstract

We study, at T=0, the anomalies in the magnetization curve of the S=1 two-leg ladder with frustrated interactions. We focus mainly on the existence of the $M=\Ms/2$ plateau, where $\Ms$ is the saturation magnetization. We use analytical methods (degenerate perturbation theory and non-Abelian bosonization) as well as numerical methods (level spectroscopy and density matrix renormalization group), which lead to the consistent conclusion with each other. We also touch on the $M=\Ms/4$ and $M=(3/4)\Ms$ plateaux and cusps.

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Tôru Sakai, Kiyomi Okamoto, Kouichi Okunishi, Masahiro Sato. 2004-12-16. Anomalous magnetization process in frustrated spin ladders. https://doi.org/10.1088/0953-8984%2F16%2F11%2F030

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