46,907 research outputs found
On the Origin of the Non-Fermi Liquid Behavior of SrRuO_{3}
Motivated by the unusual features observed in the transport properties of the
ferromagnetic "bad metal" , we construct a model incorporating
essential features of the realistic structure of this nearly cubic material. In
particular, we show how the orbital {\it orientation} in the perfectly
cubic structure determines the peculiar structure of the hybridization matrix,
and demonstrate how the local non-Fermi liquid features arise when interactions
are switched on. we discuss the effect of the slight deviation from the cubic
structure (at low-) qualitatively. The model provides a consistent
explanation of the features observed recently in the optical response of
.Comment: 4 pages. Submitted to Physical Review Letter
Interfaces between highly incompatible polymers of different stiffness: Monte Carlo simulations and self-consistent field calculations
We investigate interfacial properties between two highly incompatible
polymers of different stiffness. The extensive Monte Carlo simulations of the
binary polymer melt yield detailed interfacial profiles and the interfacial
tension via an analysis of capillary fluctuations. We extract an effective
Flory-Huggins parameter from the simulations, which is used in self-consistent
field calculations. These take due account of the chain architecture via a
partial enumeration of the single chain partition function, using chain
conformations obtained by Monte Carlo simulations of the pure phases. The
agreement between the simulations and self-consistent field calculations is
almost quantitative, however we find deviations from the predictions of the
Gaussian chain model for high incompatibilities or large stiffness. The
interfacial width at very high incompatibilities is smaller than the prediction
of the Gaussian chain model, and decreases upon increasing the statistical
segment length of the semi-flexible component.Comment: to appear in J.Chem.Phy
Calorons in SU(3) lattice gauge theory
We examine the semiclassical content of SU(3) Yang Mills theory on the
lattice at finite temperature. Employing the cooling method, a set of classical
fields is generated from a Monte Carlo ensemble. Various operators are used to
inspect this set with respect to topological properties. We find pseudoparticle
fields, so-called caloron solutions, possessing the remarkable features of
(superpositions of) Kraan-van Baal solutions, i.e. extensions of
Harrington-Shepard calorons to generic values of the holonomy.Comment: 14 pages, 16 figure
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