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arXiv · 1106.2704

Engineering steady states using jump-based feedback for multipartite entanglement generation

R. N. Stevenson·J. J. Hope·A. R. R. Carvalho
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Abstract

We investigate the use of quantum-jump-based feedback to manipulate the stability of multipartite entangled dark states in an open quantum system. Using the model proposed in Phys. Rev. A 76, 010301(R) (2007) for a pair of atoms, we show a general strategy to produce many-body singlet stationary entangled states for larger number of atoms. In the case of four qubits, we propose a simple local feedback control that, although not optimal, is realistic and stabilises a highly entangled state. We discuss the limitations and analyse alternative strategies within the framework of direct jump feedback schemes.

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R. N. Stevenson, J. J. Hope, A. R. R. Carvalho. 2011-06-14. Engineering steady states using jump-based feedback for multipartite entanglement generation. https://doi.org/10.1103/physreva.84.022332

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