Overlaps between eigenstates of the XXZ spin-1/2 chain and a class of simple product states

Pozsgai, Balázs

Published Jan 1, 2014• 93 citations

Abstract

We consider a class of quantum quenches in the spin-1/2 XXZ chain, where the initial state is of a simple product form. Specific examples are the Néel state, the dimer state and the q-deformed dimer state. We compute determinant formulas for finite volume overlaps between the initial state and arbitrary eigenstates of the spin chain Hamiltonian. These results could serve as a basis for calculating the time dependence of correlation functions following the quantum quench.

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