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arXiv · 1103.2813

Experimental realization of field-induced XY and Ising ground states in a quasi-2D S=1/2 Heisenberg antiferromagnet

Yoshimitsu Kohama. Marcelo Jaime·Oscar E. Ayala-Valenzuela·Ross D. McDonald·Eun deok Mun·Jordan F. Corbey·Jamie L. Manson
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Abstract

High field specific heat, Cp, and magnetic susceptibility, \c{hi}, measurements were performed on the quasi-two dimensional Heisenberg antiferromagnet [Cu(pyz)2(pyO)2](PF6)2. While no Cp anomaly is observed down to 0.5 K in zero magnetic field, the application of field parallel to the crystallographic ab-plane induces a lambda-like anomaly in Cp, consistent with Ising-type magnetic order. On the other hand, when the field is parallel to the c-axis, Cp and \c{hi} show evidence of XY-type antiferromagnetism. We argue that it is a small but finite easy-plane anisotropy in quasi-two dimensional [Cu(pyz)2(pyO)2](PF6)2 that allows the unusual observation of field induced XY and Ising-type magnetic states.

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Yoshimitsu Kohama. Marcelo Jaime, Oscar E. Ayala-Valenzuela, Ross D. McDonald, Eun deok Mun, Jordan F. Corbey, Jamie L. Manson. 2011-03-14. Experimental realization of field-induced XY and Ising ground states in a quasi-2D S=1/2 Heisenberg antiferromagnet. https://doi.org/10.1103/physrevb.84.184402

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