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LiV2O4: evidence for two-stage screening

J. Hopkinson·P. Coleman
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Abstract

LiV2O4, a frustrated mixed valent metal (d^1 <-> d^2), is argued to undergo two spin-screening processes. The first quenches the effective spin to produce the spin 1/2 behavior seen below room temperature[1], while the second produces the heavy fermi liquid character seen at low temperatures[2]. We present here a preliminary discussion of a t-J model with strong Hund's coupling of the strongly correlated d-electrons. Valence fluctuations of the Hubbard operators (S = {1/2} <-> 1) combined with the frustration of the underlying corner-shared tetrahedral vanadium lattice are the essential components of our model.

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J. Hopkinson, P. Coleman. 2002-02-15. LiV2O4: evidence for two-stage screening. https://doi.org/10.1016/s0921-4526(01)01477-6

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