Abstract

A major outstanding problem for many quantum clock synchronization protocols is the hidden assumption of a common phase reference between the parties to be synchronized. In general, the definition of the quantum states between two parties do not have consistent phase definitions, which can lead to an unknown systematic error. We show that despite prior arguments to the contrary, it is possible to remove this unknown phase via entanglement purification. This closes the loophole for entanglement based quantum clock synchronization protocols, which is a non-local approach to synchronize two clocks independent of the properties of the intervening medium. Starting with noisy Bell pairs, we show that the scheme produces a singlet state for any combination of (i) differing basis conventions for Alice and Bob; (ii) an overall time offset in the execution of the purification algorithm; and (iii) the presence of a noisy channel. Error estimates reveal that better performance than existing classical Einstein synchronization protocols should be achievable using current technology.

Details

Title
Remote quantum clock synchronization without synchronized clocks
Author
Ilo-Okeke, Ebubechukwu O 1 ; Tessler, Louis 2 ; Dowling, Jonathan P 3 ; Byrnes, Tim 4 

 State Key Laboratory of Precision Spectroscopy, School of Physical and Material Sciences, East China Normal University, Shanghai, China; New York University Shanghai, Pudong, Shanghai, China; Department of Physics, School of Physical Sciences, Federal University of Technology, Owerri, Nigeria 
 New York University Shanghai, Pudong, Shanghai, China; RIKEN Cluster for Pioneering Research, Wako-Shi, Saitama, Japan 
 NYU-ECNU Institute of Physics at NYU Shanghai, Shanghai, China; Hearne Institute for Theoretical Physics, Department of Physics & Astronomy, Louisiana State University, Baton Rouge, Louisiana, USA; CAS-Alibaba Quantum Computing Laboratory, University of Science and Technology of China, Shanghai, China 
 State Key Laboratory of Precision Spectroscopy, School of Physical and Material Sciences, East China Normal University, Shanghai, China; New York University Shanghai, Pudong, Shanghai, China; NYU-ECNU Institute of Physics at NYU Shanghai, Shanghai, China; National Institute of Informatics, Chiyoda-ku, Tokyo, Japan; Department of Physics, New York University, New York, NY, USA 
Pages
1-5
Publication year
2018
Publication date
Aug 2018
Publisher
Nature Publishing Group
e-ISSN
20566387
Source type
Scholarly Journal
Language of publication
English
ProQuest document ID
2088781149
Copyright
© 2018. This work is published under http://creativecommons.org/licenses/by/4.0/ (the “License”). Notwithstanding the ProQuest Terms and Conditions, you may use this content in accordance with the terms of the License.