We derive a novel multiple integral representation for a gen erating function of theσz-σz correlation functions of the spin1 2 XXZ chain at finite temperature and finite, longitudinal magnetic field.… (More)

We establish that the Yang-Baxter equations in the presence of an impurity can in general only admit solutions of simultaneous transmission and reflection when the transmission and reflection… (More)

We present two pairs of Y(sl2) Yangian symmetries for the trigonometric and hyperbolic versions of the Hubbard model with non-nearest-neighbour hopping. In both cases the Yangians are mutually… (More)

We derive finite temperature versions of integral formulae f or the two-point correlation functions in the antiferromagnetic XXZ chain. The derivation is based on the summation of density matrix… (More)

We present an integral formula for the density matrix of a fini te segment of the infinitely long spin1 2 XXZ chain. This formula is valid for any temperature and any longitudinal magnetic field.… (More)

We consider a multiple integral representation for a one-pa rameter generating function of the finite temperature Sz-Sz correlation functions of the antiferromagnetic spin-1 /2 XXZ chain in the XX… (More)

We develop a general scheme for the use of Fermi operators within the framework of integrable systems. This enables us to read off a fermionic Hamiltonian from a given solution of the Yang-Baxter… (More)

We solve the gl(1 |2) generalized model by means of the algebraic Bethe ansatz. The resulting eigenvalue of the transfer matr ix and the Bethe ansatz equations depend on three complex functions, c… (More)

We present a conjecture for the density matrix of a finite segm ent of the XXZ chain coupled to a heat bath and to a constant longitudinal magneti c fi ld. It states that the inhomogeneous density… (More)

It was recently shown by Jimbo, Miwa and Smirnov that the corr elation functions of a generalized XXZ chain associated with an inho mogeneous six-vertex model with disorder parameter α and with… (More)