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Entanglement and dynamics of spin-chains in periodically-pulsed magnetic fields: accelerator modes

T. Boness·S. Bose·T. S. Monteiro
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Abstract

We study the dynamics of a single excitation in a Heisenberg spin-chain subjected to a sequence of periodic pulses from an external, parabolic, magnetic field. We show that, for experimentally reasonable parameters, a pair of counter-propagating coherent states are ejected from the centre of the chain. We find an illuminating correspondence with the quantum time evolution of the well-known paradigm of quantum chaos, the Quantum Kicked Rotor (QKR). From this we can analyse the entanglement production and interpret the ejected coherent states as a manifestation of so-called `accelerator modes' of a classically chaotic system.

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T. Boness, S. Bose, T. S. Monteiro. 2006-03-02. Entanglement and dynamics of spin-chains in periodically-pulsed magnetic fields: accelerator modes. https://doi.org/10.1103/physrevlett.96.187201

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