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Related papers: Quantum metrology out of equilibrium

200 papers

Random and uncontrollable noises from the environment during the design and measurement of superconducting qubits lead to limitations in qubit coherence time and gate fidelity, which is a major challenge in the current state of the art for…

Quantum Physics · Physics 2025-07-09 Hamid Reza Naeij

We use contemporary quantum computers to experimentally investigate quantum steering ofan open quantum system by measurements on its environment. On three IBMQ processors wedistinguish a qubit as the open system and perform pairwise…

Quantum Physics · Physics 2023-03-28 Lennart Maximilian Seifert , Konstantin Beyer , Kimmo Luoma , Walter T. Strunz

In this paper we introduce a measure of genuine quantum incompatibility in the estimation task of multiple parameters, that has a geometric character and is backed by a clear operational interpretation. This measure is then applied to some…

Quantum Physics · Physics 2021-06-22 Federico Belliardo , Vittorio Giovannetti

In bosonic quantum metrology, the estimate of a loss parameter is typically performed by means of pure states, such as coherent, squeezed or entangled states, while mixed thermal probes are discarded for their inferior performance. Here we…

Quantum Physics · Physics 2018-10-17 Gaetana Spedalieri , Cosmo Lupo , Samuel L. Braunstein , Stefano Pirandola

We consider the problem of decoherence and relaxation of open bosonic quantum systems from a perspective alternative to the standard master equation or quantum trajectories approaches. Our method is based on the dynamics of expectation…

Quantum Physics · Physics 2009-11-13 D. A. R. Dalvit , G. P. Berman , M. Vishik

In quantum metrology quantum properties such as squeezing and entanglement are exploited in the design of a new generation of clocks, sensors and other measurement devices that can outperform their classical counterparts. Applications of…

Quantum Physics · Physics 2014-03-26 Mehdi Ahmadi , David Edward Bruschi , Ivette Fuentes

In this paper we introduce a novel noise model for quantum measurements motivated by an indirect measurement scheme with faulty preparation. Averaging over random dynamics governing the interaction between the quantum system and a probe, a…

Quantum Physics · Physics 2025-07-17 Faedi Loulidi , Ion Nechita , Clément Pellegrini

Quantum metrology studies the ultimate precision limit of physical quantities by using quantum strategy. In this paper we apply the quantum metrology technologies to the relativistic framework for estimating the deficit angle parameter of…

Quantum Physics · Physics 2022-08-11 Ying Yang , Jiliang Jing , Zehua Tian

With an ever-expanding ecosystem of noisy and intermediate-scale quantum devices, exploring their possible applications is a rapidly growing field of quantum information science. In this work, we demonstrate that variational quantum…

Quantum Physics · Physics 2021-07-16 Johannes Jakob Meyer , Johannes Borregaard , Jens Eisert

We present a description of the measurement process based on the parametric representation with environmental coherent states. This representation is specifically tailored for studying quantum systems whose environment needs being…

Quantum Physics · Physics 2015-09-30 Pietro Liuzzo-Scorpo , Alessandro Cuccoli , Paola Verrucchi

The goal of quantum metrology is to improve measurements' sensitivities by harnessing quantum resources. Metrologists often aim to maximize the quantum Fisher information, which bounds the measurement setup's sensitivity. In studies of…

Quantum Metrology is one of the most promising application of quantum technologies. The aim of this research field is the estimation of unknown parameters exploiting quantum resources, whose application can lead to enhanced performances…

Quantum Physics · Physics 2020-03-13 Emanuele Polino , Mauro Valeri , Nicolò Spagnolo , Fabio Sciarrino

Quantum metrology studies the ultimate limit of precision in estimating a physical quantity if quantum strategies are exploited. Here we investigate the evolution of a two-level atom as a detector which interacts with a massless scalar…

General Relativity and Quantum Cosmology · Physics 2015-01-28 Zehua Tian , Jieci Wang , Heng Fan , Jiliang Jing

We address the dephasing dynamics of a qubit as an effective process to estimate the temperature of its environment. Our scheme is inherently quantum, since it exploits the sensitivity of the qubit to decoherence, and does not require…

Quantum systems used for metrology can offer enhanced precision over their classical counterparts. The design of quantum sensors can be optimized by maximizing the quantum Fisher information (QFI), which characterizes the precision of…

Quantum Physics · Physics 2025-08-26 George Mihailescu , Anthony Kiely , Andrew K. Mitchell

In this work we investigate the relation between quantum measurements and decoherence, in order to formally express the necessity of the latter for obtaining an informative output from the former. To this aim, referring to the Von Neumann…

Quantum Physics · Physics 2015-06-23 Pietro Liuzzo-Scorpo , Alessandro Cuccoli , Paola Verrucchi

A usual assumption in quantum estimation is that the unknown parameter labels the possible states of the system, while it influences neither the sample space of outcomes nor the measurement aimed at extracting information on the parameter…

Quantum Physics · Physics 2017-01-18 Luigi Seveso , Matteo A. C. Rossi , Matteo G. A. Paris

Quantum metrology concerns improving the estimation of an unknown parameter using an optimal measurement scheme on the quantum system. More the optimality of the measurement, the better will be the improvement in sensing the value of the…

Quantum Physics · Physics 2025-07-30 H. S. Karthik

We provide efficient and intuitive tools for deriving bounds on achievable precision in quantum enhanced metrology based on the geometry of quantum channels and semi-definite programming. We show that when decoherence is taken into account,…

Quantum Physics · Physics 2012-09-19 Rafal Demkowicz-Dobrzanski , Jan Kolodynski , Madalin Guta

Estimation of physical parameters is a must in almost any part of science and technology. The enhancement of the performances in this task, e.g., beating the standard classical shot-noise limit, using available physical resources is a major…

Quantum Physics · Physics 2014-01-29 F. Benatti , S. Alipour , A. T. Rezakhani