Quantum Clock Synchronization with one qubit

Chris Harrelson; Iordanis Kerenidis

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Quantum Clock Synchronization with one qubit

Chris Harrelson·Iordanis Kerenidis

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Abstract

The clock synchronization problem is to determine the time difference T between two spatially separated parties. We improve on I. Chuang's quantum clock synchronization algorithm and show that it is possible to obtain T to n bits of accuracy while communicating only one qubit in one direction and using an O(2^n) frequency range. We also prove a quantum lower bound of Ω(2^n) for the product of the transmitted qubits and the range of frequencies, thus showing that our algorithm is optimal.

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Chris Harrelson, Iordanis Kerenidis. 2001-04-03. Quantum Clock Synchronization with one qubit. https://arxiv.org/abs/cs/0103021

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