Probabilistic purification of noisy coherent states

Petr Marek; Radim Filip

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arXiv · 0706.1932

Probabilistic purification of noisy coherent states

Petr Marek·Radim Filip

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Abstract

A basic feasible probabilistic purification of unknown noisy coherent states, outgoing from different state preparations with unknown mean number of thermal photons, is proposed. The scheme is based only on a linear-optical network with an avalanche photo-diode or heterodyne (homodyne) detection used to post-select a successful processing. The suggested probabilistic method can produce an output state with a lower noise than both quantum deterministic and classical probabilistic distillation method. The purification applied in the state preparation can increase classical capacity of communication and security of quantum key distribution.

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BibTeX RIS

Petr Marek, Radim Filip. 2007-06-13. Probabilistic purification of noisy coherent states. https://arxiv.org/abs/0706.1932

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