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arXiv · 1503.02501

Alternating magnetic anisotropy of Li$_2$(Li$_{1-x}T_x$)N with $T$ = Mn, Fe, Co, and Ni

A. Jesche·L. Ke·J. L. Jacobs·B. Harmon·R. S. Houk·P. C. Canfield
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Abstract

Substantial amounts of the transition metals Mn, Fe, Co, and Ni can be substituted for Li in single crystalline Li$_2$(Li$_{1-x}T_x$)N. Isothermal and temperature-dependent magnetization measurements reveal local magnetic moments with magnitudes significantly exceeding the spin-only value. The additional contributions stem from unquenched orbital moments that lead to rare-earth-like behavior of the magnetic properties. Accordingly, extremely large magnetic anisotropies have been found. Most notably, the magnetic anisotropy alternates as easy-plane $\rightarrow$ easy-axis $\rightarrow$ easy-plane $\rightarrow$ easy-axis when progressing from $T$ = Mn $\rightarrow$ Fe $\rightarrow$ Co $\rightarrow$ Ni. This behavior can be understood based on a perturbation approach in an analytical, single-ion model. The calculated magnetic anisotropies show a surprisingly good agreement with the experiment and capture the basic features observed for the different transition metals.

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A. Jesche, L. Ke, J. L. Jacobs, B. Harmon, R. S. Houk, P. C. Canfield. 2015-06-08. Alternating magnetic anisotropy of Li$_2$(Li$_{1-x}T_x$)N with $T$ = Mn, Fe, Co, and Ni. https://doi.org/10.1103/physrevb.91.180403

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