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arXiv · 0904.2580

Antiferromagnetism in the magnetoelectric effect single crystal LiMnPO$_4$

Jiying Li·Wei Tian·Ying Chen·Jerel L. Zarestky·Jeffrey W. Lynn·David Vaknin
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Abstract

Elastic and inelastic neutron scattering studies reveal details of the antiferromagnetic tansition and intriguing spin-dynamics in the magneto-electric effect single crystal LiMnPO$_4$. The elastic scattering studies confirm the system is antiferromagnetic (AFM) below $T_N$=33.75 K with local magnetic moments (Mn$^{2+}$; $S = 5/2$) that are aligned along the crystallographic a-axis. The spin-wave dispersion curves propagating along the three principal axes, determined by inelastic scattering, are adequately modeled in the linear spin-wave framework assuming a spin-Hamiltonian that is parameterized by inter- and in-plane nearest- and next-nearest-neighbor interactions, and by easy-plane anisotropy. The temperature dependence of the spin dynamics makes this an excellent model many-body spin system to address the question of the relationship between spin-wave excitations and the order parameter.

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Jiying Li, Wei Tian, Ying Chen, Jerel L. Zarestky, Jeffrey W. Lynn, David Vaknin. 2009-04-16. Antiferromagnetism in the magnetoelectric effect single crystal LiMnPO$_4$. https://doi.org/10.1103/physrevb.79.144410

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