aqora

Comparison of the magnetic properties of the Hubbard Hamiltonian in the weak correlation limit to the HFA

L. C. Bartel, H. S. Jarret

Conference on Multimedia ModelingJan 1, 19740 citations

Comparison of the magnetic properties of the Hubbard Hamiltonian in the weak correlation limmit to the HFA

L. C. Bartel, Howard S. Jarrett

Resonance broadening is included along with spin‐disorder scattering to study the magnetic properties of the Hubbard Hamiltonian in the weak correlation limit. The calculated susceptibility is compared to the exchange enhanced Hartree–Fock approximation (HFA) susceptibility, and limits are set on the applicability of the HFA. For a semicircular density of states, HFA appears to be applicable for I/Δ<0.5 and a half‐filled band, but for low electron (or hole) densities the range of applicability in I/Δ decreases.Resonance broadening is included along with spin‐disorder scattering to study the magnetic properties of the Hubbard Hamiltonian in the weak correlation limit. The calculated susceptibility is compared to the exchange enhanced Hartree–Fock approximation (HFA) susceptibility, and limits are set on the applicability of the HFA. For a semicircular density of states, HFA appears to be applicable for I/Δ<0.5 and a half‐filled band, but for low electron (or hole) densities the range of applicability in I/Δ decreases.

AIP conference proceedingsJan 1, 19750 citations

Magnetic properties of the hubbard model with strong interaction

V. Ya. Krivnov, Alexander A. Ovchinnikov, Vladyslav O. Cheranovskii

Synthetic MetalsJun 1, 19911 citation

To the Correlation Effects of the Antiferromagnetic Phase in the Hubbard Model

G. Z. Wei, H. Q. Nie, K. Y. Zhang

physica status solidi (b)Oct 1, 19911 citation

The derivation of the analytic expressions of the dynamical susceptibility based on the Hubbard-Hirsch Hamiltonian

B E Iyorsor, Robinson O. Okanigbuan, Joa Idiodi

Investigation have been carried out on the spin wave energy of a ferromagnet using the random-phase approximation (RPA) in the Stoner model. Based on the Hubbard-Hirsch Hamiltonian, in this paper we study the spin excitation in an itinerant-electron system with the Hartree-Fock Approximation (HFA) to derive the analytic expressions of the dynamical susceptibility of the spin system, by setting up the equation of motion and solving it in a generalized HFA of the susceptibility tensor, Χ-+, and quoting the result for the first derivative of the Green's function. Journal of the Nigerian Association of Mathematical Physics Vol. 10 2006: pp. 579-582Investigation have been carried out on the spin wave energy of a ferromagnet using the random-phase approximation (RPA) in the Stoner model. Based on the Hubbard-Hirsch Hamiltonian, in this paper we study the spin excitation in an itinerant-electron system with the Hartree-Fock Approximation (HFA) to derive the analytic expressions of the dynamical susceptibility of the spin system, by setting up the equation of motion and solving it in a generalized HFA of the susceptibility tensor, Χ-+, and quoting the result for the first derivative of the Green's function. Journal of the Nigerian Association of Mathematical Physics Vol. 10 2006: pp. 579-582

Journal of the Nigerian Association of Mathematical PhysicsMay 22, 20080 citations

Ising expansion for the Hubbard model

Zhu-Pei Shi, Rajiv R. P. Singh

We develop series expansions for the ground state properties of the Hubbard model by introducing an Ising anisotropy into the Hamiltonian. For the two-dimensional square lattice half-filled Hubbard model, the ground state energy, local moment, sublattice magnetization, uniform magnetic susceptibility, and spin stiffness are calculated as a function of U/t, where U is the Coulomb constant and t is the hopping parameter. Magnetic susceptibility data indicate a crossover around U\ensuremath{\approxeq}4 between spin density wave antiferromagnetism and Heisenberg antiferromagnetism. Comparisons with Monte Carlo simulations, random phase approximation result, and mean-field solutions are also made.We develop series expansions for the ground state properties of the Hubbard model by introducing an Ising anisotropy into the Hamiltonian. For the two-dimensional square lattice half-filled Hubbard model, the ground state energy, local moment, sublattice magnetization, uniform magnetic susceptibility, and spin stiffness are calculated as a function of U/t, where U is the Coulomb constant and t is the hopping parameter. Magnetic susceptibility data indicate a crossover around U\ensuremath{\approxeq}4 between spin density wave antiferromagnetism and Heisenberg antiferromagnetism. Comparisons with Monte Carlo simulations, random phase approximation result, and mean-field solutions are also made.

arXiv:cond-mat/9507096Physical review. B, Condensed matterOct 1, 19958 citations

Comparison of the magnetic properties of the Hubbard hamiltonian in the weak correlation limit to the HFA. [Susceptibility; density of states; spin-spin correlation]

Related papers

Comparison of the magnetic properties of the Hubbard hamiltonian in the weak correlation limit to the HFA. [Susceptibility; density of states; spin-spin correlation]

Related papers