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Related papers: True Limits to Precision via Unique Quantum Probe

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Preserving the precision of the parameter of interest in the presence of environmental decoherence is an important yet challenging task in dissipative quantum sensing. In this work, we study quantum metrology when the decoherence effect is…

Quantum Physics · Physics 2024-11-05 Jing Yang

We explore the physical limits of pulsed dynamical decoupling methods for decoherence control as determined by finite timing resources. By focusing on a decohering qubit controlled by arbitrary sequences of $\pi$-pulses, we establish a…

Quantum Physics · Physics 2011-04-11 Kaveh Khodjasteh , Tamás Erdélyi , Lorenza Viola

Entangled states can potentially be used to outperform the standard quantum limit which every classical sensor is bounded by. However, entangled states are very susceptible to decoherence, and so it is not clear whether one can really…

Quantum Physics · Physics 2015-05-27 Yuichiro Matsuzaki , Simon C. Benjamin , Joseph Fitzsimons

Quantum instruments are mathematical devices introduced to describe the conditional state change during a quantum process. They are completely positive map valued measures on measurable spaces. We may also view them as non-commutative…

Operator Algebras · Mathematics 2025-09-17 B. V. Rajarama Bhat , Arghya Chongdar , Sruthymurali

Quantum mechanics predicts that measurements of incompatible observables carry a minimum uncertainty which is independent of technical deficiencies of the measurement apparatus or incomplete knowledge of the state of the system. Nothing yet…

Quantum Physics · Physics 2013-06-14 Davide Girolami , Tommaso Tufarelli , Gerardo Adesso

Quantum metrology aims to exploit quantum phenomena to overcome classical limitations in the estimation of relevant parameters. We consider a probe undergoing a phase shift $\varphi$ whose generator is randomly sampled according to a…

Quantum Physics · Physics 2017-06-07 Rozhin Yousefjani , Rosanna Nichols , Shahriar Salimi , Gerardo Adesso

Precision measurements of frequency are critical to accurate timekeeping, and are fundamentally limited by quantum measurement uncertainties. While for time-independent quantum Hamiltonians, the uncertainty of any parameter scales at best…

Quantum Physics · Physics 2017-11-08 M. Naghiloo , A. N. Jordan , K. W. Murch

Quantum entanglement manifests as a distinctive correlation between particles that transcends classical boundaries when their quantum states cannot be described independently. On the other hand, as quantum systems interact with their…

Quantum Physics · Physics 2025-08-21 Samuel Marquez Gonzalez

Quantum sensors and qubits are usually two-level systems (TLS), the quantum analogs of classical bits which assume binary values '0' or '1'. They are useful to the extent to which they can persist in quantum superpositions of '0' and '1' in…

Quantum Physics · Physics 2024-01-19 A. Beckert , M. Grimm , N. Wili , R. Tschaggelar , G. Jeschke , G. Matmon , S. Gerber , M. Müller , G. Aeppli

High-frequency mechanical oscillators with long coherence times are essential to realizing a variety of high-fidelity quantum sensors, transducers, and memories. However, the unprecedented coherence times needed for quantum applications…

The study of environmentally induced superselection and of the process of decoherence was originally motivated by the search for the emergence of classical behavior out of the quantum substrate, in the macroscopic limit. This limit, and…

Quantum Physics · Physics 2009-10-30 J. R. Anglin , J. P. Paz , W. H. Zurek

Quantum spectroscopy with single two level systems has considerably improved our ability to detect weak signals. Recently it was realized that for classical signals, precision and resolution of quantum spectroscopy is limited mainly by…

Quantum Physics · Physics 2018-08-01 Tuvia Gefen , Maxim Khodas , Liam P. McGuinness , Fedor Jelezko , Alex Retzker

We use Deutsch's algorithm as a stand in for more complex quantum algorithms in order to determine how quantum properties of an environment manifest themselves in results that can be obtained on quantum computers. We model pure dephasing in…

Quantum Physics · Physics 2026-05-20 Małgorzata Strzałka , Katarzyna Roszak

We investigate the estimation of dephasing-induced decoherence in continuous-variable quantum systems using non-Gaussian probe states. By purifying the open system, we identify optimal probes, specifically squeezed cat and symmetric…

Quantum Physics · Physics 2026-01-27 Arman , Prasanta K. Panigrahi

The problem of measurement is often considered as an inconsistency inside the quantum formalism. Many attempts to solve (or to dissolve) it have been made since the inception of quantum mechanics. The form of these attempts depends on the…

Quantum Physics · Physics 2016-04-20 Herve Zwirn

Decoherence and imperfect control are crucial challenges for quantum technologies. Common protection strategies rely on noise temporal autocorrelation, which is not optimal if other correlations are present. We develop and demonstrate…

Quantum Physics · Physics 2026-01-28 Alon Salhov , Qingyun Cao , Jianming Cai , Alex Retzker , Fedor Jelezko , Genko Genov

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

This paper studies quantum limits to dynamical sensors in the presence of decoherence. A modified purification approach is used to obtain tighter quantum detection and estimation error bounds for optical phase sensing and optomechanical…

Quantum Physics · Physics 2013-07-04 Mankei Tsang

Quantum metrology is a promising practical use case for quantum technologies, where physical quantities can be measured with unprecedented precision. In lieu of quantum error correction procedures, near term quantum devices are expected to…

Quantum Physics · Physics 2021-12-03 Yingkai Ouyang , Nathan Shettell , Damian Markham

We exhibit three inequalities involving quantum measurement, all of which are sharp and state independent. The first inequality bounds the performance of joint measurement. The second quantifies the trade-off between the measurement quality…

Quantum Physics · Physics 2021-08-18 Bas Janssens