Approaching the Limit of Quantum Clock Precision

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.

Source: arXiv:2604.22704v1 - http://arxiv.org/abs/2604.22704v1 PDF: https://arxiv.org/pdf/2604.22704v1 Original Link: http://arxiv.org/abs/2604.22704v1