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arXiv · 1206.4597

Magnetic transitions and magnetodielectric effect in the antiferromagnet SrNdFeO$_4$

J. M. Hwang·E. S. Choi·H. D. Zhou·Y. Xin·J. Lu·P. Schlottmann
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Abstract

We investigated the magnetic phase diagram of single crystals of SrNdFeO$_{4}$ by measuring the magnetic properties, the specific heat and the dielectric permittivity. The system has two magnetically active ions, Fe$^{3+}$ and Nd$^{3+}$. The Fe$^{3+}$ spins are antiferromagnetically ordered below 360 K with the moments lying in the ab-plane, and undergo a reorientation transition at about 35-37 K to an antiferromagnetic order with the moments along the c-axis. A short-range, antiferromagnetic ordering of Nd$^{3+}$ along the c-axis was attributed to the reorientation of Fe$^{3+}$ followed by a long-range ordering at lower temperature [S. Oyama {\it et al.} J. Phys.: Condens. Matter. {\bf 16}, 1823 (2004)]. At low temperatures and magnetic fields above 8 T, the Nd$^{3+}$ moments are completely spin-polarized. The dielectric permittivity also shows anomalies associated with spin configuration changes, indicating that this compound has considerable coupling between spin and lattice. A possible magnetic structure is proposed to explain the results.

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J. M. Hwang, E. S. Choi, H. D. Zhou, Y. Xin, J. Lu, P. Schlottmann. 2012-06-20. Magnetic transitions and magnetodielectric effect in the antiferromagnet SrNdFeO$_4$. https://doi.org/10.1103/physrevb.85.224429

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