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Related papers: Coherent measurements in quantum metrology

200 papers

Coherence and entanglement are fundamental properties of quantum systems, promising to power the near future quantum computers, sensors and simulators. Yet, their experimental detection is challenging, usually requiring full reconstruction…

Quantum Physics · Physics 2017-08-01 Graeme Smith , John A. Smolin , Xiao Yuan , Qi Zhao , Davide Girolami , Xiongfeng Ma

Correlations between spacelike separated measurements on entangled quantum systems are stronger than any classical correlations and are at the heart of numerous quantum technologies. In practice, however, spacelike separation is often not…

Quantum Physics · Physics 2017-11-28 Martin Ringbauer , Rafael Chaves

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

The measurement postulate of quantum theory stands in conflict with the laws of thermodynamics and has evoked debate regarding what actually constitutes a measurement. With the help of modern quantum statistical mechanics, we take the first…

Quantum Physics · Physics 2025-12-16 Emanuel Schwarzhans , Felix C. Binder , Marcus Huber , Maximilian P. E. Lock

Precision metrology underpins scientific and technological advancements. Quantum metrology offers a pathway to surpass classical sensing limits by leveraging quantum states and measurement strategies. However, measuring multiple…

In this paper, we present a thought experiment that demonstrates that the equivalence of quantum reduced states and statistical mixed states of ensembles is not merely a simple mathematical formulation in quantum mechanics, but rather…

Quantum Physics · Physics 2025-04-18 Zhihong Zuo

We propose a solid-state experiment to study the process of continuous quantum measurement of a qubit state. The experiment would verify that an individual qubit stays coherent during the process of measurement (in contrast to the gradual…

Mesoscale and Nanoscale Physics · Physics 2009-10-31 Alexander N. Korotkov

The geometry of quantum states provides a unifying framework for estimation processes based on quantum probes, and it allows to derive the ultimate bounds of the achievable precision. We show a relation between the statistical distance…

Quantum Physics · Physics 2016-11-28 Paolo Giorda , Michele Allegra

Endeavoring to formulate an exhaustive solution to the measurement problem in view of the theory of decoherence leads to a better understanding of the status of the collapse and of the emergence of classicality, thanks to a precise…

Quantum Physics · Physics 2023-09-01 Antoine Soulas

Entanglement does not describe all quantum correlations and several authors have shown the need to go beyond entanglement when dealing with mixed states. Various different measures have sprung up in the literature, for a variety of reasons,…

Quantum Physics · Physics 2023-01-23 Aharon Brodutch , Kavan Modi

Incompatibility of certain measurements -- impossibility of obtaining deterministic outcomes simultaneously -- is a well known property of quantum mechanics. This feature can be utilized in many contexts, ranging from Bell inequalities to…

Quantum Physics · Physics 2018-03-14 Martin Plesch , Matej Pivoluska

Quantum metrology seeks to leverage the richness of quantum systems for making better measurements than are possible using only classical resources in order to gain a ``quantum advantage''. Quantum metrology schemes must also be resilient…

We analyze the effects of quantum correlations, such as entanglement and discord, on the efficiency of phase estimation by studying four quantum circuits that can be readily implemented using NMR techniques. These circuits define a standard…

Quantum Physics · Physics 2012-01-04 Kavan Modi , Hugo Cable , Mark Williamson , Vlatko Vedral

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

Quantum metrology studies quantum strategies which enable us to outperform their classical counterparts. In this framework, the existence of perfect classical reference frames is usually assumed. However, such ideal reference frames might…

Quantum Physics · Physics 2015-03-17 Dominik Šafránek , Mehdi Ahmadi , Ivette Fuentes

Quantum metrology pursues high-precision measurements of physical quantities by using quantum resources. However, the decoherence generally hinders its performance. Previous work found that the metrological error tends to diverge in the…

Quantum Physics · Physics 2021-11-04 Wei Wu , Jun-Hong An

Quantum phenomena offer the possibility of measuring physical quantities with precision beyond classical limits. However, current progress is constrained by scalability, environmental noise, and challenges in practical integration. This…

Quantum Physics · Physics 2025-10-24 George Mihailescu , Uesli Alushi , Roberto Di Candia , Simone Felicetti , Karol Gietka

This dissertation studies the statistics and modeling of a quantum system probed by a coherent laser field. We focus on an ensemble of qubits dispersively coupled to a traveling wave light field. The first research topic explores the…

Quantum Physics · Physics 2013-01-29 Robert L. Cook

Quantum systems in nonequilibrium conditions, where coherent many-body interactions compete with dissipative effects, can feature rich phase diagrams and emergent critical behavior. Associated collective effects, together with the…

Quantum Physics · Physics 2026-01-28 Robert Mattes , Albert Cabot , Federico Carollo , Igor Lesanovsky

Quantum measurement is a fundamental cornerstone of experimental quantum computations. The main issues in current quantum measurement strategies are the high number of measurement rounds to determine a global optimal measurement output and…

Quantum Physics · Physics 2019-05-02 Laszlo Gyongyosi , Sandor Imre