Kondo destruction and valence fluctuations in an Anderson model
Abstract
Unconventional quantum criticality in heavy-fermion systems has been extensively analyzed in terms of a critical destruction of the Kondo effect. Motivated by a recent demonstration of quantum criticality in a mixed-valent heavy-fermion system, \beta-YbAlB4, we study a particle-hole-asymmetric Anderson impurity model with a pseudogapped density of states. We demonstrate Kondo destruction at a mixed-valent quantum critical point, where a collapsing Kondo energy scale is accompanied by a singular charge-fluctuation spectrum. Both spin and charge responses scale with energy over temperature (\omega/T) and magnetic field over temperature (H/T). Implications for unconventional quantum criticality in mixed-valence heavy fermions are discussed.
Keywords
Cite
@article{arxiv.1108.5227,
title = {Kondo destruction and valence fluctuations in an Anderson model},
author = {J. H. Pixley and Stefan Kirchner and Kevin Ingersent and Qimiao Si},
journal= {arXiv preprint arXiv:1108.5227},
year = {2012}
}
Comments
5 pages, 5 figures, discussion on the implications for quantum criticality of the beta-YbAlB4 system is expanded; to appear in PRL