113 research outputs found
Composite Spin-Triplet Superconductivity in an Symmetric Lattice Model
The two-channel Anderson lattice model which has
symmetry is of relevance to understanding of the magnetic, quadrupolar and
superconducting phases in UThBe or Pr base skutterudite
compounds such as PrFeP or PrOsSb. Possible
unconventional superconducting phases of the model are explored. They are
characterized by a composite order parameter comprising of a local magnetic or
quadrupolar moment and a triplet conduction electron Cooper-pair. This binding
of local degrees of freedom removes the entropy of the non Fermi-liquid normal
state. We find superconducting transitions in the intermediate valence regime
which are suppressed in the stable moment regime. The gap function is non
analytic and odd in frequency: a pseudo-gap develops in the conduction electron
density of states which vanishes as close to . In the
strong intermediate valent regime, the gap function acquires an additional
\k-dependence.Comment: 20 pages, 12 figures, latex EPJ format. Accepted for publication as
Eur.Phys.J.
Comment on "Scaling feature of magnetic field induced Kondo-peak splittings"
In a recent work Zhang and coworkers (PRB 82, 075111 (2010)) studied the
Zeeman splitting of the Kondo resonance for the single impurity Anderson model
in a finite magnetic field with the numerical renormalization group (NRG)
method. There, it was found that with increasing magnetic field the
position of the Kondo resonance in the total spectral function \textit{does
not} approach its position in the spin resolved spectral function.
Additionally, the position of the Kondo maximum exceeded the Zeeman energy for
, where is the low energy Kondo scale of the model
(, ). In this comment we argue that both these findings
are produced by an improper choice of NRG parameter values. However, we
reproduce the crossover in the splitting from Kondo-like behavior to a
non-universal splitting larger than the Zeeman energy, but this crossover
occurs at much larger fields of the order of the charge scale.Comment: Minor revisions; same version as publishe
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