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Multi-particle decoherence free subspaces in extended systems

Raisa I. Karasik·Karl-Peter Marzlin·Barry C. Sanders·K. Birgitta Whaley
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Abstract

We develop a method to determine spatial configurations to realize decoherence-free subspaces for spatially extended multi-particle systems. We have assumed normal reservoir behavior including translational invariance of the reservoir and preparation in stationary states or mixture thereof and weak Markovian system-reservoir coupling that requires energy transfer. One important outcome of our method is a proof that there does not exist a multi-particle decoherence-free subspace in such systems except in the limit that the spatial extent of the system becomes infinitesimal.

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Raisa I. Karasik, Karl-Peter Marzlin, Barry C. Sanders, K. Birgitta Whaley. 2007-02-26. Multi-particle decoherence free subspaces in extended systems. https://doi.org/10.1103/physreva.76.012331

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