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arXiv · 0908.1244

Anomalous metallic state in the vicinity of Metal to Valence Bond Solid insulator transition in LiVS2

N. Katayama·M. Uchida·D. Hashizume·S. Niitaka·J. Matsuno·D. Matsumura·Y. Nishihata·J. Mizuki·N. Takeshita·A. Gauzzi·M. Nohara·H. Takagi
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Abstract

We investigate LiVS2 and LiVSe2 with a triangular lattice as itinerant analogues of LiVO2, known for the formation of valence bond solid (VBS) state out of S = 1 frustrated magnet. LiVS2, which is located at the border between a metal and a correlated insulator, shows a first ordered transition from a paramagnetic metal to a VBS insulator at Tc ~ 305 K upon cooling. The presence of VBS state in the close vicinity of insulator-metal transition may suggest the importance of itinerancy in the formation of VBS state. We argue that the high temperature metallic phase of LiVS2 has a pseudo-gap, likely originating from the VBS fluctuation. LiVSe2 was found to be a paramagnetic metal down to 2 K.

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N. Katayama, M. Uchida, D. Hashizume, S. Niitaka, J. Matsuno, D. Matsumura, Y. Nishihata, J. Mizuki, N. Takeshita, A. Gauzzi, M. Nohara, H. Takagi. 2009-08-09. Anomalous metallic state in the vicinity of Metal to Valence Bond Solid insulator transition in LiVS2. https://doi.org/10.1103/physrevlett.103.146405

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