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arXiv · 0901.3568

Eavesdropping of two-way coherent-state quantum cryptography via Gaussian quantum cloning machines

Stefano Pirandola·Stefano Mancini·Seth Lloyd·Samuel L. Braunstein
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Abstract

We consider one of the quantum key distribution protocols recently introduced in Ref. [Pirandola et al., Nature Physics 4, 726 (2008)]. This protocol consists in a two-way quantum communication between Alice and Bob, where Alice encodes secret information via a random phase-space displacement of a coherent state. In particular, we study its security against a specific class of individual attacks which are based on combinations of Gaussian quantum cloning machines.

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Stefano Pirandola, Stefano Mancini, Seth Lloyd, Samuel L. Braunstein. 2009-01-22. Eavesdropping of two-way coherent-state quantum cryptography via Gaussian quantum cloning machines. https://doi.org/10.1109/icqnm.2009.8

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