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arXiv · 1904.02353

Blind quantum computation with a heralded single photon source

Kurumiko Nagao·Tomoyuki Horikiri·Toshihiko Sasaki
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Abstract

Blind quantum computation is a scheme that adds unconditional security to cloud quantum computation. In the protocol proposed by Broadbent, Fitzsimons, and Kashefi, the ability to prepare and transmit a single qubit is required for a user (client) who uses a quantum computer remotely. In case a weak coherent pulse is used as a pseudo single photon source, however, we must introduce decoy states, owing to the inherent risk of transmitting multiple photon. In this study, we demonstrate that by using a heralded single photon source and a probabilistic photon number resolving detector, we can gain a higher blind state generation efficiency and longer access distance, owing to noise reduction on account of the heralding signal.

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Kurumiko Nagao, Tomoyuki Horikiri, Toshihiko Sasaki. 2019-04-04. Blind quantum computation with a heralded single photon source. https://doi.org/10.1103/physreva.99.042324

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