Exact density matrix for quantum group invariant sector of XXZ model

Fedor Smirnov (1)

1 LPTHE - Laboratoire de Physique Théorique et Hautes Energies

Using the fermionic basis we obtain the expectation values of all $U_q(\slt)$-invariant local operators on 8 sites for the anisotropic six-vertex model on a cylinder with generic Matsubara data. In the case when the $U_q(\slt)$ symmetry is not broken this computation is equivalent to finding the entire density matrix up to 8 sites. As application, we compute the entanglement entropy without and with temperature, and compare the results with CFT predictions.

Mots clés: density matrix; model: vertex; numerical calculations; temperature: 0; quantum group; field theory: conformal; XXZ model; entropy: entanglement

Domaines: Physique mathématique [math-ph]; Physique Générale [physics.gen-ph]; Physique des Hautes Energies - Théorie [hep-th]

Fedor Smirnov. Exact density matrix for quantum group invariant sector of XXZ model. 2018. ⟨hal-01792267⟩