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Orbitally Driven Spin Pairing in the 3D Non-Magnetic Mott Insulator BaVS3: Evidence from Single Crystal Studies

G. Mihaly·I. Kezsmarki·F. Zamborszky·M. Miljak·K. Penc·P. Fazekas·H. Berger·L. Forro
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Abstract

Static electrical and magnetic properties of single crystal BaVS_3 were measured over the structural (T_S=240K), metal-insulator (T_MI=69K), and suspected orbital ordering (T_X=30K) transitions. The resistivity is almost isotropic both in the metallic and insulating states. An anomaly in the magnetic anisotropy at T_X signals a phase transition to an ordered low-T state. The results are interpreted in terms of orbital ordering and spin pairing within the lowest crystal field quasi-doublet. The disordered insulator at T_X<T<T_MI is described as a classical liquid of non-magnetic pairs.

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G. Mihaly, I. Kezsmarki, F. Zamborszky, M. Miljak, K. Penc, P. Fazekas, H. Berger, L. Forro. 2000-01-28. Orbitally Driven Spin Pairing in the 3D Non-Magnetic Mott Insulator BaVS3: Evidence from Single Crystal Studies. https://doi.org/10.1103/physrevb.61.r7831

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