A selection of papers presented at the VII International Conference on Quantum Technologies (ICQT-2023, July 9-12, 2023, Moscow)

Modeling of correlated systems using the fluctuating local field method on the example of two-dimensional Hubbard lattices

Ya. S. Lyakhova^ab, A. N. Rubtsov<sup>ac

a</sup> Russian Quantum Center, Skolkovo, Moscow
^b National Research Nuclear University MEPhI
^c Lomonosov Moscow State University

Abstract: The work is dedicated to the development of the fluctuating local field method for modeling correlated systems in the moderate correlation regime. The two-stage scheme is elaborated, according to which one uses the fluctuating local field method to construct an effective small parameter in the system. Then one develops the perturbation theory with respect to this small parameter. This scheme is applied to modeling of the two-dimensional Hubbard lattices. The results of our computations are in a good accordance with the computationally exact results. The presented method can be applied to the description of many-particles quantum systems, such as high-temperature superconductors, spin liquids and atoms in optical lattices.

Keywords: correlated systems, fluctuations, Hubbard model.

Received: 08.12.2023
Revised: 28.12.2023
Accepted: 01.02.2024