Single-Particle Excitations in Narrow Energy Bands

Single-Particle Excitations in Narrow Energy Bands

Hubbard's model for studying correlation effects in systems with narrow energy bands is analyzed by means of a technique which allows the calculation of moments of the individual peaks in the spectral weight function for single-particle excitations. The analysis of the zeroth moments of the peaks shows that the total weight in the bands depends on the strength of the kinetic-energy term in the ...

Electron Correlations in Narrow Energy Bands

Single Particle Excitations in the E8 Ising Model

We present analytic expressions for the single particle excitation energies of the 8 quasi–particles in the lattice E8 Ising model and demonstrate that all excitations have an extended Brillouin zone which, depending on the excitation, ranges from 0 < P < 4π to 0 < P < 12π. These are compared with exact diagonalizations for systems through size 10 and with the E8 fermionic representations of th...

Single Particle Excitations in the Lattice E8 Ising Model

We present analytic expressions for the single particle excitation energies of the 8 quasi-particles in the lattice E8 Ising model and demonstrate that all excitations have an extended Brillouin zone which, depending on the excitation, ranges from 0 < P < 4π to 0 < P < 12π. These are compared with exact diagonalizations for systems through size 10 and with the E8 fermionic representations of th...

Low-frequency excitations in a molecular glass: Single-particle dynamics.

The low-frequency dynamics of a molecular glass former has been investigated by means of inelastic neutron scattering &om a mostly incoherent sample as well as by computer molecular-dynamics simulation. The mode assignments have been carried out using the neutron data for the polycrystal as well as by means of the analysis of the density of states (DOS) computed from a lattice-dynamics calculat...