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Interaction-free generation of entanglement

Hiroo Azuma
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Abstract

In this paper, we study how to generate entanglement by interaction-free measurement. Using Kwiat et al.'s interferometer, we construct a two-qubit quantum gate that changes a particle's trajectory according to the other particle's trajectory. We propose methods for generating the Bell state from an electron and a positron and from a pair of photons by this gate. We also show that using this gate, we can carry out the Bell measurement with the probability of 3/4 at the maximum and execute a controlled-NOT operation by the method proposed by Gottesman and Chuang with the probability of 9/16 at the maximum. We estimate the success probability for generating the Bell state by our procedure under imperfect interaction.

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Hiroo Azuma. 2003-09-05. Interaction-free generation of entanglement. https://doi.org/10.1103/physreva.68.022320

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