Competition between Quadrupole and Magnetic Kondo Effects in Non-Kramers Doublet Systems
Abstract
We discuss possible competition between magnetic and quadrupole Kondo effects in non-Kramers doublet systems under cubic symmetry. The quadrupole Kondo effect leads to non-Fermi-liquid (NFL) ground state, while the magnetic one favors ordinary Fermi liquid (FL). In terms of the - coupling scheme, we emphasize that the orbital fluctuation must develop in the vicinity of the NFL-FL boundary. We demonstrate a change of behavior in the f-electron entropy by the Wilson's numerical renormalization-group (NRG) method on the basis of the extended two-channel Kondo exchange model. We present implications to extensively investigated PrTX (T=Ti, V, Ir; X=Al, Zn) systems that exhibit both quadrupole ordering and peculiar superconductivity. We also discuss the magnetic-field effect which lifts weakly the non-Kramers degeneracy. Our model also represents the FL state accompanied by a free magnetic spin as a consequence of stronger competition between the magnetic and the quadrupole Kondo effects.
Keywords
Cite
@article{arxiv.1409.3061,
title = {Competition between Quadrupole and Magnetic Kondo Effects in Non-Kramers Doublet Systems},
author = {Hiroaki Kusunose and Takahiro Onimaru},
journal= {arXiv preprint arXiv:1409.3061},
year = {2015}
}
Comments
10 pages, 5 figures, SCES2014 conference proceedings