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arXiv · 1404.6439

Experimental Realization of a Quantum Breathing Pyrochlore Antiferromagnet

K. Kimura·S. Nakatsuji·T. Kimura
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Abstract

The synthesis and characterization of a new Yb-based material Ba3Yb2Zn5O11 are reported. This material is identified as the first model system of a pseudospin-1/2 quantum antiferromagnet on "breathing" pyrochlore lattice characterized by an alternating array of small and large Yb tetrahedra. Despite dominant antiferromagnetic interactions J ~ 7 K, a large amount of magnetic entropy (25%) remains at 0.38 K, indicating that each small Yb tetrahedron forms a unique doubly degenerate singlet state. These results are well described by the Heisenberg pseudospin-1/2 single tetrahedron model.

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K. Kimura, S. Nakatsuji, T. Kimura. 2014-04-25. Experimental Realization of a Quantum Breathing Pyrochlore Antiferromagnet. https://doi.org/10.1103/physrevb.90.060414

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