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arXiv · 1802.10242

Structural Disorder and Elementary Magnetic Properties of Triangular Lattice ErMgGaO4 Single Crystals

F. Alex Cevallos·Karoline Stolze·Robert J. Cava
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Abstract

The single crystal growth, structure, and basic magnetic properties of ErMgGaO4 are reported. The structure consists of triangular layers of magnetic ErO6 octahedra separated by a double layer of randomly occupied non-magnetic (Ga,Mg)O5 bipyramids. The Er atoms are positionally disordered. Magnetic measurements parallel and perpendicular to the c axis of a single crystal reveal dominantly antiferromagnetic interactions, with a small degree of magnetic anisotropy. A weighted average of the directional data suggests an antiferromagnetic Curie Weiss temperature of approximately -30 K. Below 10 K the temperature dependences of the inverse susceptibilities in the in-plane and perpendicular-to plane directions are parallel, indicative of an isotropic magnetic moment at low temperatures. No sign of magnetic ordering is observed above 1.8 K, suggesting that ErMgGaO4 is a geometrically frustrated magnet.

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F. Alex Cevallos, Karoline Stolze, Robert J. Cava. 2018-02-28. Structural Disorder and Elementary Magnetic Properties of Triangular Lattice ErMgGaO4 Single Crystals. https://doi.org/10.1016/j.ssc.2018.03.015

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