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Positioning and clock synchronization through entanglement

Vittorio Giovannetti·Seth Lloyd·Lorenzo Maccone
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Abstract

A method is proposed to employ entangled and squeezed light for determining the position of a party and for synchronizing distant clocks. An accuracy gain over analogous protocols that employ classical resources is demonstrated and a quantum-cryptographic positioning application is given, which allows only trusted parties to learn the position of whatever must be localized. The presence of a lossy channel and imperfect photodetection is considered. The advantages in using partially entangled states is discussed.

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Vittorio Giovannetti, Seth Lloyd, Lorenzo Maccone. 2002-01-11. Positioning and clock synchronization through entanglement. https://doi.org/10.1103/physreva.65.022309

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