Study of strongly correlated electron systems in infinite dimensions

Marcelo J. Rozenberg

Tetsuro Saso, 哲郎 佐宗

Yury Anatolievich Krotov

Götz Möller, Andrei E. Ruckenstein, Stefan Schmitt-Rink

We study the simplest nontrivial model that describes a basic feature of strongly correlated systems, namely, the transfer of spectral weight between high- and low-energy excitations. We use the limit of infinite dimensions to calculate exactly the corresponding single-particle and optical-conductivity spectra. We comment on the relevance of these results to a recently proposed scenario for the breakdown of Fermi-liquid theory in strongly correlated metals.

H. Schweitzer, G. Czycholl

Qian‐Qian Shi, Sheng-Hao Li, Jianhui Zhao +1 more

An algorithm to find a graded Projected Entangled-Pair State representation of the ground state wave functions is developed for translationally invariant strongly correlated electronic systems on infinite-size lattices in two spatial dimensions. It is tested for the two-dimensional t-J model at and away from half filling, with truncation dimensions up to 6. We are able to locate a line of phase separation, which qualitatively agrees with the results based on the high-temperature expansions. We find that the model exhibits an extended s-wave superconductivity for J=0.4t at quarter filling. However, we emphasize that the currently accessible truncation dimensions are not large enough, so it is necessary to incorporate the symmetry of the system into the algorithm, in order to achieve results with higher precision.