The BCS model and the off shell Bethe ansatz for vertex models
نویسندگان
چکیده
We study the connection between the BCS pairing model and the inhomogeneous vertex model. The two spectral problems coincide in the quasi–classical limit of the off–shell Bethe Ansatz of the disordered six vertex model. The latter problem is transformed into an auxiliary spectral problem which corresponds to the diagonalization of the integrals of motion of the BCS model. A generating functional whose quasi classical expansion leads to the constants of motion of the BCS model and in particular the Hamiltonian, is identified. PACS: 03.65.Fd, 74.20.Fg
منابع مشابه
6 J ul 2 00 1 The BCS model and the off shell Bethe ansatz for vertex models
We study the connection between the BCS pairing model and the inhomogeneous vertex model. The two spectral problems coincide in the quasi– classical limit of the off–shell Bethe Ansatz of the disordered six vertex model. The latter problem is transformed into an auxiliary spectral problem which corresponds to the diagonalization of the integrals of motion of the BCS model. A generating function...
متن کاملAlgebraic Bethe ansatz for a class of coupled asymmetric six - vertex free - fermion model M . J . Martins
We present an algebraic Bethe ansatz for certain submanifolds of the bilayer vertex models proposed by Shiroishi and Wadati as coupled asymmetric six-vertex free-fermion models. A peculiar feature of our formulation is the presence of a diagonal monodromy matrix element that does not generate unwanted terms. The model contains two free-parameters entering into the Bethe ansatz equations as a pu...
متن کاملThermodynamics and Form Factors of Supersymmetric Integrable Field Theories
We study on-shell and off-shell properties of the supersymmetric sinh-Gordon and perturbed SUSY Yang-Lee models using the thermodynamic Bethe ansatz and form factors. Identifying the supersymmetric models with the Eight Vertex Free Fermion Model, we derive inversion relation for inhomogeneous transfer matrix and TBA equations and get correct UV results. We obtain two-point form factors of the t...
متن کاملPseudo-differential equations, and the Bethe Ansatz for the classical Lie algebras
The correspondence between ordinary differential equations and Bethe ansatz equations for integrable lattice models in their continuum limits is generalised to vertex models related to classical simple Lie algebras. New families of pseudo-differential equations are proposed, and a link between specific generalised eigenvalue problems for these equations and the Bethe ansatz is deduced. The pseu...
متن کاملThe matrix product ansatz for the six - vertex model
Recently it was shown that the eigenfunctions for the the asymmetric exclusion problem and several of its generalizations as well as a huge family of quantum chains, like the anisotropic Heisenberg model, Fateev-Zamolodchikov model, Izergin-Korepin model, Sutherland model, t − J model, Hubbard model, etc, can be expressed by a matrix product ansatz. Differently from the coordinate Bethe ansatz,...
متن کامل