The Hartree-Fock ground-state phase diagram of the one-dimensional Hubbard model is calculated in the μ−U plane, restricted to phases with no charge density modulation. This allows antiferromagnetism, saturated ferromagnetism, spiral spin density waves and a collinear structure with unit cell ↑↑↓↓. The spiral phase is unstable against phase separation near quarter-, halfand three-quarter-fillin...

Given a dataset of 3D points in which there is hole , i.e., region with lack information, we develop method providing surface that fits the and fills hole. The filling patch required to fulfill prescribed volume condition. fitting-filling function consists radial basis functions minimizes an energy functional involving both, fitting constraint patch, as well fairness function. We give convergen...

Via measurements of commensurability features near the Landau filling factor ν=1/2, we probe the shape of the Fermi contour for hole-flux composite fermions confined to a wide GaAs quantum well. The data reveal that the composite fermions are strongly influenced by the characteristics of the Landau level in which they are formed. In particular, their Fermi contour is warped when their Landau le...

We have studied a Kondo hole in a one-dimensional Kondo insulator at half-filling using a density matrix formulation of the numerical renormalization group. The Kondo hole introduces midgap states. The spin density introduced by the hole is localized in the vicinity of the hole. It resides primarily in the f spins for small exchange coupling J and in the conduction spins for large J . We presen...

We report on a study of the charged-skyrmion or spin-texture excitations which occur in quantum Hall ferromagnets near odd Landau level filling factors. Particle-hole symmetry is used to relate the spin-quantum numbers of charged particle and hole excitations and neutral particle-hole pair excitations. Hartree-Fock theory is used to provide quantitative estimates of the energies of these excita...

To understand the essence of the exciton Mott transition in three-dimensional electron-hole systems, the metalinsulator transition is studied for a two-band Hubbard model in infinite dimensions with interactions of electronelectron (hole-hole) repulsion U and electron-hole attraction −U . By using the dynamical mean-field theory, the phase diagram in the U -U ′ plane is obtained (which is exact...