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The "topological" charge for the finite XX quantum chain

Ulrich Bilstein·Vladimir Rittenberg
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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.

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Ulrich Bilstein, Vladimir Rittenberg. 2000-04-14. The "topological" charge for the finite XX quantum chain. https://doi.org/10.1088/0305-4470%2F33%2F42%2F101

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