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On the origin of heavy quasiparticles in LiV_2O_4

P. Fulde·A. N. Yaresko·A. A. Zvyagin·Y. Grin
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Abstract

An explanation is provided for the heavy quasiparticle excitations in LiV_2O_4. It differs considerably from that of other known heavy-fermion systems. Main ingredients of our theory are the cubic spinel structure of the material and strong short-range correlations of the d electrons. The large gamma-coefficient is shown to result from excitations of Heisenberg spin 1/2 rings and chains. The required coupling constant is calculated from LDA+U calculations and is found to be of the right size. Also the calculated Sommerfeld-Wilson ratio is reasonably close to the observed one.

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P. Fulde, A. N. Yaresko, A. A. Zvyagin, Y. Grin. 2001-01-30. On the origin of heavy quasiparticles in LiV_2O_4. https://doi.org/10.1209/epl%2Fi2001-00322-3

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