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Integrability of a disordered Heisenberg spin-1/2 chain

L. F. santos
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Abstract

We investigate how the transition from integrability to nonintegrability occurs by changing the parameters of the Hamiltonian of a Heisenberg spin-1/2 chain with defects. Randomly distributed defects may lead to quantum chaos. A similar behavior is obtained in the presence of a single defect out of the edges of the chain, suggesting that randomness is not the cause of chaos in these systems, but the mere presence of a defect.

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L. F. santos. 2003-10-02. Integrability of a disordered Heisenberg spin-1/2 chain. https://doi.org/10.1088/0305-4470%2F37%2F17%2F004

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