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arXiv · 2608.07938

Quantum Chinese Remainder Clock

Ivri Nagar·Alioscia Hamma·Mikel Palmero·Matthew Radzihovsky·Shouzhuo Yang·Seth Lloyd
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Abstract

The Chinese remainder theorem is used in metrology for extending the range of quantum clocks/radar/interferometry, where the phase of a signal is known relative to a set of oscillators with different periods. This paper investigates the performance of a quantum-mechanical Chinese remainder clock, consisting of atoms/oscillators with pairwise coprime periods. We provide the optimal initial state and the optimal Heisenberg-limited quantum measurements for measuring time up to the product of the periods. We introduce a novel fault-tolerant post-processing protocol that allows reconstruction of the correct time even in the presence of errors in the remainders.

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Ivri Nagar, Alioscia Hamma, Mikel Palmero, Matthew Radzihovsky, Shouzhuo Yang, Seth Lloyd. 2026-08-08. Quantum Chinese Remainder Clock. https://arxiv.org/abs/2608.07938

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