On correlation functions of integrable models associated to the six-vertex R-matrix

TL;DR

This paper extends the master equation approach to a broad class of integrable models related to the six-vertex R-matrix, enabling new integral representations of correlation functions, exemplified by the quantum non-linear Schrödinger model.

Contribution

It generalizes the master equation method to continuum and lattice models associated with the six-vertex R-matrix, providing a unified framework for correlation functions.

Findings

Derived a generalized master equation for integrable models

Obtained multiple integral representations for correlation functions

Applied to quantum non-linear Schrödinger model

Abstract

We derive an analog of the master equation obtained recently for correlation functions of the XXZ chain for a wide class of quantum integrable systems described by the R-matrix of the six-vertex model, including in particular continuum models. This generalized master equation allows us to obtain multiple integral representations for the correlation functions of these models. We apply this method to derive the density-density correlation functions of the quantum non-linear Schrodinger model.