Physics – Condensed Matter – Strongly Correlated Electrons
Scientific paper
2007-12-13
Phys. Rev. B 77, 134439 (2008)
Physics
Condensed Matter
Strongly Correlated Electrons
11 pages, 7 figs; (v2) small changes, additional refs, final version as published
Scientific paper
10.1103/PhysRevB.77.134439
The unconventional critical behavior near magnetic quantum phase transitions in various heavy-fermion metals, apparently inconsistent with the standard spin-density-wave scenario, has triggered proposals on the breakdown of the Kondo effect at the critical point. Here we investigate, within one specific scenario, the fate of such a zero-temperature transition upon coupling of the electronic to lattice degrees of freedom. We study a Kondo-Heisenberg model with volume-dependent Kondo coupling -- this model displays both Kondo volume collapse and Kondo-breakdown transitions, as well as Lifshitz transitions associated with a change of the Fermi-surface topology. Within a large-N treatment, we find that the Lifshitz transition tends to merge with the Kondo volume collapse and hence becomes first order, whereas the Kondo breakdown transition remains of second order except for very soft lattices. Interesting physics emerges at the zero-temperature endpoint of the Kondo volume collapse: For electrons in two space dimensions, this endpoint is located at the Lifshitz line for a large range of parameters, thus two continuous quantum phase transitions coincide without fine tuning. We analyze the effective Landau theory for such a situation and discuss critical exponents. Finally, we relate our findings to current heavy-fermion experiments.
Hackl Andreas
Vojta Matthias
No associations
LandOfFree
Kondo volume collapse, Kondo breakdown, and Fermi surface transitions in heavy-fermion metals does not yet have a rating. At this time, there are no reviews or comments for this scientific paper.
If you have personal experience with Kondo volume collapse, Kondo breakdown, and Fermi surface transitions in heavy-fermion metals, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Kondo volume collapse, Kondo breakdown, and Fermi surface transitions in heavy-fermion metals will most certainly appreciate the feedback.
Profile ID: LFWR-SCP-O-622820