Quantum critical properties of the Bose-Fermi Kondo Model in a large-N limit

dc.creatorZhu, Lijun
dc.creatorKirchner, Stefan
dc.creatorSi, Qimiao
dc.creatorGeorges, Antoine
dc.date2004-06-14
dc.date2005-01-06
dc.date.accessioned2026-07-25T23:12:36Z
dc.descriptionStudies of non-Fermi liquid properties in heavy fermions have led to the current interest in the Bose-Fermi Kondo model. Here we use a dynamical large-N approach to analyze an SU(N)xSU($κN$) generalization of the model. We establish the existence in this limit of an unstable fixed point when the bosonic bath has a sub-ohmic spectrum ($|ω|^{1-ε} \sgn ω$, with $0<ε<1$). At the quantum critical point, the Kondo scale vanishes and the local spin susceptibility (which is finite on the Kondo side for κ<1) diverges. We also find an ω/T scaling for an extended range (15 decades) of ω/T. This scaling violates (for $ε\ge 1/2$) the expectation of a naive mapping to certain classical models in an extra dimension; it reflects the inherent quantum nature of the critical point.
dc.description4 pages; v2: included clarifying discussions on why the omega/T scaling (for epsilon >=1/2) violates the naive mapping to classical models in an extra dimension and the implications of this observation about the nature of the QCP; v3: shortened to conform to the PRL length limit
dc.identifierhttps://arxiv.org/abs/cond-mat/0406293
dc.identifierhttp://arxiv.org/abs/cond-mat/0406293
dc.identifierPhys.Rev.Lett. 93, 267201(2004)
dc.identifierdoi:10.1103/PhysRevLett.93.267201
dc.identifier.urihttps://dspace.dare.co.zw/handle/123456789/96474
dc.subjectStrongly Correlated Electrons
dc.titleQuantum critical properties of the Bose-Fermi Kondo Model in a large-N limit
dc.typetext

Files