Progress of Theoretical Physics Supplement
Electron Correlations in the High-Dimension Hubbard Model
H. Hasegawa
Abstract
The effect of electron correlations in the infinite-dimension (d=∞) Hubbard model at finite temperatures has been investigated with the use of a theory which was recently proposed by the present author generalizing the slave-boson functional-integral method. Sublattice magnetizations, double occupancies and band-narrowing factors are computed as functions of the interaction, U, and the temperature, T. Calculated results are exact in the limits of U→0 and U→∞, and in the limits of T=0 and T→∞ they are expected to be very accurate owing to the nature of our mean-field-type theory for infinite-dimension systems. Similarities and differences between the calculated results for d=3 and d=∞ are also discussed.