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arXiv · 0909.0832

Reducing quantum control for spin-spin entanglement distribution

Francesco Ciccarello·Mauro Paternostro·G. Massimo Palma·M. Zarcone
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Abstract

We present a protocol that sets maximum stationary entanglement between remote spins through scattering of mobile mediators without initialization, post-selection or feedback of the mediators' state. No time-resolved tuning is needed and, counterintuitively, the protocol generates two-qubit singlet states even when classical mediators are used. The mechanism responsible for such effect is resilient against non-optimal coupling strengths and dephasing affecting the spins. The scheme uses itinerant particles and scattering centres and can be implemented in various settings. When quantum dots and photons are used a striking result is found: injection of classical mediators, rather than quantum ones, improves the scheme efficiency.

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Francesco Ciccarello, Mauro Paternostro, G. Massimo Palma, M. Zarcone. 2010-01-30. Reducing quantum control for spin-spin entanglement distribution. https://doi.org/10.1088/1367-2630%2F11%2F11%2F113053

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