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State permutations from manipulation of near level-crossings

Nicole F. Bell·R. F. Sawyer·Raymond R. Volkas·Yvonne Y. Y. Wong
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Abstract

We discuss some systematic methods for implementing state manipulations in systems formally similar to chains of a few spins with nearest-neighbor interactions, arranged such that there are strong and weak scales of coupling links. States are permuted by means of bias potentials applied to a few selected sites. This generic structure is then related to an atoms-in-a-cavity model that has been proposed in the literature as a way of achieving a decoherence free subspace. A new method using adiabatically varying laser detuning to implement a CNOT gate in this model is proposed.

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Nicole F. Bell, R. F. Sawyer, Raymond R. Volkas, Yvonne Y. Y. Wong. 2003-06-19. State permutations from manipulation of near level-crossings. https://doi.org/10.1103/physreva.68.032307

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