1,467 research outputs found
The Fermi surface and the role of electronic correlations in SmCeCuO
Using LDA+GTB (local density approximation+generalized tight-binding) hybrid
scheme we investigate the band structure of the electron-doped high-
material SmCeCuO. Parameters of the minimal tight-binding
model for this system (the so-called 3-band Emery model) were obtained within
the NMTO (-th order Muffin-Tin orbital) method. Doping evolution of the
dispersion and Fermi surface in the presence of electronic correlations was
investigated in two regimes of magnetic order: short-range (spin-liquid) and
long-range (antiferromagnetic metal). Each regime is characterized by the
specific topologies of the Fermi surfaces and we discuss their relation to
recent experimental data.Comment: 10 pages, 4 figures, 1 table, Published versio
Topological stripelike coreless textures with inner incommensurability in two-dimensional Heisenberg antiferromagnet
For two-dimensional Heisenberg antiferromagnet we present an analysis of
topological coreless excitations having a stripe form. These textures are
characterized by singularities at boundaries. A detailed classification of the
stripe textures results in a certain analogy with the coreless excitations in
phase: Mermin-Ho and Anderson-Toulouse coreless vortices. The
excitations of the last type may have a low bulk energy. The stripe textures
may be observed as an occurrence of short-range incommensurate order in the
antiferromagnetic environment
- …