On the origin of heavy quasiparticles in LiV_2O_4
arXiv:cond-mat/0101455 · doi:10.1209/epl/i2001-00322-3
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.
REVTEX, 5 pages, 2 figures