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Microscopic Theory of Magnetic Phase Transitions in HoNi_2B_2C

A. Amici·P. Thalmeier
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Abstract

We present a microscopic theory for the low temperature metamagnetic phase diagram of HoNi_2B_2C that agrees well with experiments.For the same model we determined the zero field ground state as a function of temperature and find the $c$-axis commensurate to incommensurate transition in the expected temperature range. The complex behaviour of the system originates from the competition between the crystalline electric field and the Ruderman-Kittel-Kasuya-Yosida interaction, whose effective form is obtained. No essential influence of superconductivity has to be invoked to understand the magnetic phase diagram of this material.

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A. Amici, P. Thalmeier. 1998-05-05. Microscopic Theory of Magnetic Phase Transitions in HoNi_2B_2C. https://doi.org/10.1103/physrevb.57.10684

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