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Suppression of decoherence via strong intra-environmental coupling

L. Tessieri·J. Wilkie
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Abstract

We examine the effects of intra-environmental coupling on decoherence by constructing a low temperature spin--spin-bath model of an atomic impurity in a Debye crystal. The impurity interacts with phonons of the crystal through anti-ferromagnetic spin-spin interactions. The reduced density matrix of the central spin representing the impurity is calculated by dynamically integrating the full Schroedinger equation for the spin--spin-bath model for different thermally weighted eigenstates of the spin-bath. Exact numerical results show that increasing the intra-environmental coupling results in suppression of decoherence. This effect could play an important role in the construction of solid state quantum devices such as quantum computers.

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L. Tessieri, J. Wilkie. 2002-07-09. Suppression of decoherence via strong intra-environmental coupling. https://doi.org/10.1088/0305-4470/36/49/012

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