3 research outputs found
Transverse Spin Diffusion in a Dilute Spin-Polarized Degenerate Fermi Gas
We re-examine the calculation of the transverse spin-diffusion coefficient in
a dilute degenerate spin-polarized Fermi gas, for the case of s-wave
scattering. The special feature of this limit is that the dependence of the
spin diffusion coefficient on temperature and field can be calculated
explicitly with no further approximations. This exact solution uncovers a novel
intermediate behavior between the high field spin-rotation dominated regime in
which , , and the
low-field isotropic, collision dominated regime with . In this intermediate regime, but . We also present an analytical
calculation of the self-energy in the s-wave approximation for a dilute
spin-polarized Fermi gas, at zero temperature. This emphasizes the failure of
the conventional Fermi-liquid phase space arguments for processes involving
spin flips. We close by reviewing the evidence for the existence of the
intermediate regime in experiments on weakly spin-polarized and
mixtures.Comment: 38 pages, Latex-Revtex, 9 PostScript figures. Minor revisions,
misprints corrected, references adde
Inhomogeneous Phases in a Double-Exchange Magnet with Long Range Coulomb Interactions
We consider a model with competing double-exchange (ferromagnetic) and
super-exchange (anti-ferromagnetic) interactions in the regime where phase
separation takes place. The presence of a long range Coulomb interaction
frustrates a macroscopic phase separation, and favors microscopically
inhomogeneous configurations. We use the variational Hartree-Fock approach, in
conjunction with Monte-Carlo simulations to study the geometry of such
configurations in a two-dimensional system. We find that an array of diamond
shaped ferromagnetic droplets is the preferred configuration at low electronic
densities, while alternating ferromagnetic and anti-ferromagnetic diagonal
stripes emerge at higher densities. These findings are expected to be relevant
for thin films of colossal magneto-resistive manganates.Comment: 15 pages, 9 figures. Journal Ref. added, errors correcte
Erratum to: Measurements of Ξ− and Ξ ¯+ production in proton–proton interactions at √sN N = 17.3 GeV in the NA61/SHINE experiment
his Erratum replaces incorrect plots shown in Fig. 7 with the corrected ones. In the publication, the NA57 [1] ratios of Ξ− and Ξ¯¯¯¯+ to the number of wounded nucleons at ⟨NW⟩=349 by mistake were plotted at the wrong values. The ratios were calculated and plotted by mistake using ⟨NW⟩=249.
The correct normalization does not change the conclusions of the paper. The correctly normalized results are presented in Fig. 7