Briefly: P&C Board is seeking manuscript reviewers for APA journals

Singlet–triplet transition in lateral quantum dots: A numerical renormalization group study

“…( 11) which vanishes in the infinite band width limit. In our calculations, the Kondo temperature is comparable to the bandwidth D. Furthermore, on the triplet side of the transition the convergence to the ground state is rather slow due to the large ferromagnetic residual exchange coupling, generic to underscreened Kondo models, that can even lead to singular non-Fermi liquid properties 37 . Therefore we cannot use the Friedel sum rule to determine the conductivity of the dot.…”

Non-Fermi-liquid behavior from two-dimensional antiferromagnetic fluctuations: A renormalization-group and large-Nanalysis

“…As we shall see in the following section, a numerical solution of the EDMFT equations for the Kondo lattice using an approximate "impurity solver" based on the large-N expansion leads to a similar conclusion: only subdominant corrections to the Landau damping rate are generated instead of the anomalous (power-law like) enhancement observed experimentally. It has been recently argued 14,18 that the understanding of non-Fermi liquid behavior in heavy-fermion compounds close to a QCP requires a formalism in which electronic degrees of freedom and spin fluctuations can be treated on the same footing, at least as a starting point. This is a non-trivial task, which is however made easier in the context of the extended dynamical mean-field theory (EDMFT) 15,16,17 of the Kondo lattice model, which we consider here.…”

“…It has been recently argued 14,18 that the understanding of non-Fermi liquid behavior in heavy-fermion compounds close to a QCP requires a formalism in which electronic degrees of freedom and spin fluctuations can be treated on the same footing, at least as a starting point. This is a non-trivial task, which is however made easier in the context of the extended dynamical mean-field theory (EDMFT) 15,16,17 of the Kondo lattice model, which we consider here.…”

“…This was first proposed 3,6 as a phenomenological fit to the inelastic neutron scattering data in the form: 14 have further developed this point of view in the framework of the extended dynamical mean-field (EDMFT) theory of the Kondo lattice 15,16,17 . It has been argued in this context that the separation of electronic degrees of freedom and long-wavelength magnetic fluctuations is not legitimate 14,18 , because the (Kondo) coherence scale below which electron degrees of freedom can be eliminated might vanish at the QCP. Recently however, Grempel and Si showed 19 that starting above the Kondo temperature the EDMFT of the Kondo lattice can be mapped, using bosonization tricks, onto the EDMFT of the φ 4 theory for magnetic modes (see also the earlier work by Sengupta and one of us 17 ).…”

Resonating valence-bond theory of superconductivity for dopant carriers: Application to the cobaltates

“…Such a representation makes unnecessary the choice between a bosonic and fermionic spin and is most suitable to describe the coexistence of strong magnetic correlations within a paramagnetic phase. Besides, it has been demonstrated 16 that thus defined supersymmeric Hubbard operators prove to be very efficient in treating the physics of the infinite U Hubbard model.…”