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Related papers: Approaching the Limit of Quantum Clock Precision

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Quantum clock synchronization (QCS) aims to establish a shared temporal reference between distant nodes by exploiting uniquely quantum phenomena such as entanglement, single-photon interference, and quantum correlations. In contrast to…

In order to unitarily evolve a quantum system, an agent requires knowledge of time, a parameter which no physical clock can ever perfectly characterise. In this letter, we study how limitations on acquiring knowledge of time impact…

Quantum Physics · Physics 2023-10-24 Jake Xuereb , Florian Meier , Paul Erker , Mark T. Mitchison , Marcus Huber

Understanding how to tailor quantum dynamics to achieve a desired evolution is a crucial problem in almost all quantum technologies. We present a very general method for designing high-efficiency control sequences that are always fully…

Quantum Physics · Physics 2020-03-30 Thales Figueiredo Roque , Aashish A. Clerk , Hugo Ribeiro

The ability to measure, hold and distribute time with high precision and accuracy is a foundational capability for scientific exploration. Beyond fundamental science, time synchronization is an indispensable feature of public and private…

Quantum Physics · Physics 2022-10-03 James Troupe , Stav Haldar , Ivan Agullo , Paul Kwiat

The exquisite control exhibited over quantum states of individual particles has revolutionized the field of precision measurement, as exemplified by the most accurate atomic clock realized in single trapped ions. Whereas many-atom lattice…

We consider a periodic quantum clock based on cooperative resonance fluorescence at zero temperature. In the quantum case, this system has an exact steady state and the limit cycle appears in conditional quantum dynamics under homodyne…

Quantum Physics · Physics 2025-03-18 Varinder Singh , Euijoon Kwon , G J Milburn

Many efforts have succeeded over the last decade at lengthening the timescale in which spin qubits loss quantum information under free evolution. With these design principles at a mature stage, it is now timely to widen the scope and take…

Quantum Physics · Physics 2024-07-31 Luis Escalera-Moreno

We introduce the concept of an entangled clock, where the flow of time is operationally defined by the discrete registration of measurement outcomes on a singlet state. Comparing the synchronization rate of two such clocks against classical…

Quantum Physics · Physics 2025-12-12 Karl Svozil

Thermal machines are physical systems designed to convert thermal energy into practical work through cyclic state transformations. A key component in such a machine is a clock-equipped control element that dictates which interaction…

Understanding different aspects of time is at the core of many areas in theoretical physics. Minimal models of continuous stochastic and quantum clocks have been proposed to explore fundamental limitations on the performance of timekeeping…

Quantum Physics · Physics 2026-03-31 Ludmila Viotti , Marcus Huber , Rosario Fazio , Gonzalo Manzano

Continuous-time stochastic processes pervade everyday experience, and the simulation of models of these processes is of great utility. Classical models of systems operating in continuous-time must typically track an unbounded amount of…

Quantum Physics · Physics 2018-03-05 Thomas J. Elliott , Mile Gu

We report that entangled pairs of quantum clocks (non-degenerate quantum bits) can be used as a specialized detector for precisely measuring difference of proper-times that each constituent quantum clock experiences. We describe why the…

Quantum Physics · Physics 2009-11-06 W. Y. Hwang , D. Ahn , S. W. Hwang , Y. D. Han

We consider an isolated autonomous quantum machine, where an explicit quantum clock is responsible for performing all transformations on an arbitrary quantum system (the engine), via a time-independent Hamiltonian. In a general context, we…

Quantum Physics · Physics 2015-06-30 Artur S. L. Malabarba , Anthony J. Short , Philipp Kammerlander

Quantum entanglement offers powerful opportunities for enhancing measurement sensitivity beyond classical limits, with optical atomic clocks serving as a leading platform for such advances. This chapter introduces the principles of…

Quantum Physics · Physics 2025-12-04 Raphael Kaubruegger , Adam M. Kaufman

Atomic clocks are crucial for science and technology, but their sensitivity is often restricted by the standard quantum limit. To surpass this limit, correlations between particles or interrogation times must be leveraged. Although the…

Quantum Physics · Physics 2024-10-28 Chengyin Han , Zhu Ma , Yuxiang Qiu , Ruihuan Fang , Jiatao Wu , Chang Zhan , Maojie Li , Jiahao Huang , Bo Lu , Chaohong Lee

The origin and nature of time in complex systems is explored using quantum (or 'Feynman') clocks and the signals produced by them. Networks of these clocks provide the basis for the evolution of complex systems. The general concept of…

General Relativity and Quantum Cosmology · Physics 2007-05-23 Scott Hitchcock

We introduce a novel algorithm for the task of coherently controlling a quantum mechanical system to implement any chosen unitary dynamics. It performs faster than existing state of the art methods by one to three orders of magnitude…

Quantum Physics · Physics 2015-06-04 Pierre de Fouquieres

Clock synchronization is critical for maintaining low error rates in quantum key distribution. Here, we describe how a frequency mismatch between the transmitter and receiver clocks affects the quantum bit error rate in quantum key…

Quantum Physics · Physics 2026-05-27 Loïc Millet , Boris Korzh , Rob Thew , Gianluca Boso

Controlled quantum machines have matured significantly. A natural next step is to increasingly grant them autonomy, freeing them from time-dependent external control. For example, autonomy could pare down the classical control wires that…

We propose powering a quantum clock with the non-thermal resources offered by the stationary state of an integrable quantum spin chain, driven out of equilibrium by a quench in a parameter of our choice. Analyzing the bias conditions of the…

Quantum Physics · Physics 2024-12-18 Daniele Nello , Alessandro Silva