The "topological" charge for the finite XX quantum chain

Abstract

It is shown that an operator (in general non-local) commutes with the Hamiltonian describing the finite XX quantum chain with certain non-diagonal boundary terms. In the infinite volume limit this operator gives the "topological" charge.

5 pages

References in corpus (2)

• The XX--model with boundaries. Part I: Diagonalization of the finite chain
• The XX-model with boundaries. Part II: Finite size scaling and partition functions

Cited by in corpus (2)

• Magic in the spectra of the XXZ quantum chain with boundaries at Delta=0 and Delta=-1/2
• Exact solution of the open XXZ chain with general integrable boundary terms at roots of unity