SINGLE-PARTICLE EXCITATION SPECTRUM OF THE HUBBARD-MODEL WITH MAGNETIC FRUSTRATION AT FINITE-TEMPERATURE

The single-particle excitation spectrum of the Hubbard model with magn etic frustration at finite temperature is examined using numerical exa ct diagonalization techniques. The magnetic frustration is introduced by a proper choice of the Hamiltonian parameters, which lead to rich l ow-energy spin excitation behavior, resembling those observed in heavy fermion systems. At finite temperature, the low-lying excited states become thermally populated with significant weight. As a result, the c alculated spectrum shows interesting temperature dependent evolution. The calculated results are presented and discussed in a many-body pict ure to gain insight into the photoelectron spectroscopy of strongly co rrelated electron systems.