Work

Correlation functions of the six-vertex IRF model and its quantum spin chain

Year: 2024

Type: article

Abstract: We consider the interaction-round-a-face version of the isotropic six-vertex model. The associated spin chain is made of two coupled Heisenberg spin chains with different boundary twists. The phase diagram of the model and the long distance correlations were studied in Tavares and Ribeiro (2023) [43] . Here, we compute the short-distance correlation functions of the model in the ground state for finite system sizes via non-linear integral equations and in the thermodynamic limit. This was possible since the model satisfies the face version of the discrete quantum Knizhnik-Zamolodchikov (qKZ) equation. A suitable ansatz for the density matrix is proposed in the form of a direct sum of two Heisenberg density matrices, which allows us to obtain the discrete functional equation for the two-site function ω ( λ 1 , λ 2 ) . Thanks to the known results on the factorization of correlation functions of the Heisenberg chain, we are able to compute the density matrix of the IRF model for up to four sites and its associated spin chain for up to three sites.

Source: Nuclear Physics B

DOI: 10.1016/j.nuclphysb.2024.116715

Authors: T.S. Tavares, G.A.P. Ribeiro

Institutions: Universidade de São Paulo, Universidade Federal de São Carlos

Language: English

Topic: Quantum many-body systems

Subfield: Atomic and Molecular Physics, and Optics

Field: Physics and Astronomy

Domain: Physical Sciences

Open Access status: diamond

Funder: Fundação de Amparo à Pesquisa do Estado de São Paulo

Award: Physical properties of integrable quantum spin chain and integrable classical models