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arXiv · 2604.22704

Approaching the Limit of Quantum Clock Precision

Chad Nelmes·Emanuel Schwarzhans·Tony Apollaro·Timothy Spiller·Irene D'Amico
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Abstract

Precise and autonomous clocks are of fundamental interest and central importance to both foundational studies and practical applications. Here, we construct a blueprint for a quantum clock governed by time-independent interactions. By carefully-engineered coherent transport in dissipative spin chains, we achieve a scaling exponent at the precision-resolution trade-off fundamental bound, bringing this within reach of physically realistic and experimentally accessible systems. We further introduce a sudden-quench protocol that enables repeated operation through a simple initialization and detachment mechanism. Remarkably, the protocol is robust to imprecise detachment timing, implying that high-precision timekeeping can be achieved even when driven by a clock with much lower precision.

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Chad Nelmes, Emanuel Schwarzhans, Tony Apollaro, Timothy Spiller, Irene D'Amico. 2026-04-24. Approaching the Limit of Quantum Clock Precision. https://arxiv.org/abs/2604.22704

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