collaborators

6 papers

math-ph2025

All correlation functions of the open XXX spin 1/2 quantum chains for unparallel boundary magnetic fields with one constraint

G. Niccoli

In this first paper, we start the analysis of correlation functions of quantum spin chains with general integrable boundary conditions. We initiate these computations for the open…

math-ph2025

Non-diagonal open spin-1/2 XXZ quantum chains by separation of variables: Complete spectrum and matrix elements of some quasi-local operators

G. Niccoli

The integrable quantum models, associated to the transfer matrices of the 6-vertex reflection algebra for spin 1/2 representations, are studied in this paper. In the framework of S…

math-ph2025

On correlation functions for the open XXZ chain with non-longitudinal boundary fields : the case with a constraint

G. Niccoli, V. Terras

This paper is a continuation of [1], in which a set of matrix elements of local operators was computed for the XXZ spin-1/2 open chain with a particular case of unparallel boundary…

math-ph2025

Correlation functions for open XXZ spin 1/2 quantum chains with unparallel boundary magnetic fields

G. Niccoli, V. Terras

In this paper we continue our derivation of the correlation functions of open quantum spin 1/2 chains with unparallel magnetic fields on the edges; this time for the more involved…

math-ph2025

The open XYZ spin 1/2 chain: Separation of Variables and scalar products for boundary fields related by a constraint

G. Niccoli, V. Terras

We consider the open XYZ spin chain with boundary fields. We solve the model by the new Separation of Variables approach introduced in arXiv:1904.00852. In this framework, the tran…

math-ph2025

On correlation functions of the open XYZ spin 1/2 chain with boundary fields related by a constraint

G. Niccoli, V. Terras

In this paper, we consider the quantum XYZ open spin-1/2 chain with boundary fields. We focus on the particular case in which the six boundary parameters are related by a single co…