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Related papers: Quantum Metrology: Dynamics vs. Entanglement

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We study the exact solution for a two-mode model describing coherent coupling between atomic and molecular Bose-Einstein condensates (BEC), in the context of the Bethe ansatz. By combining an asymptotic and numerical analysis, we identify…

Statistical Mechanics · Physics 2009-11-07 Huan-Qiang Zhou , Jon Links , Ross H. McKenzie

The stability of colliding Bose-Einstein condensates is investigated. A set of coupled Gross-Pitaevskii equations is thus considered, and analyzed via a perturbative approach. No assumption is made on the signs (or magnitudes) of the…

Other Condensed Matter · Physics 2009-11-11 I. Kourakis , P. K. Shukla , M. Marklund , L. Stenflo

The concept of entanglement entropy appears in multiple contexts, from black hole physics to quantum information theory, where it measures the entanglement of quantum states. We investigate the entanglement entropy in a simple model, the…

Mesoscale and Nanoscale Physics · Physics 2015-05-13 Karyn Le Hur

In the context of measurement-induced entanglement phase transitions, the influence of quantum noises, which are inherent in real physical systems, is of great importance and experimental relevance. In this Letter, we present a…

Quantum Physics · Physics 2024-06-17 Shuo Liu , Ming-Rui Li , Shi-Xin Zhang , Shao-Kai Jian

Quantum effects in a system of coupled atomic and molecular Bose-Einstein condensates in the framework of a two-mode model are studied numerically and analytically, using the discrete WKB approach. In contrast to the mean-field…

Other Condensed Matter · Physics 2007-05-23 J. Dorignac , Yu. B. Gaididei , J. C. Eilbeck , P. L. Christiansen , C. Katerji

Protocols for quantum measurement are an essential part of quantum computing. Measurements are no longer confined to the final step of computation but are increasingly embedded within quantum circuits as integral components of…

Quantum Physics · Physics 2025-11-07 Michal Krejčí , Lucie Krejčí , Ijaz Ahamed Mohammad , Martin Plesch , Martin Friák

Entanglement is a fundamental feature of quantum mechanics, considered a key resource in quantum information processing. Measuring entanglement is an essential step in a wide range of applied and foundational quantum experiments. When a…

Quantum effects in metrology can in principle enhance measurement precision from the so-called standard quantum limit to the Heisenberg Limit. Further advancements in quantum metrology largely rely on innovative metrology protocols that can…

Quantum Physics · Physics 2025-06-16 Zhixing Zou , Jiangbin Gong , Weitao Chen

Quantum resources, such as entanglement, can decrease the uncertainty of a parameter-estimation procedure beyond what is classically possible. This phenomenon is well described for noiseless systems with asymptotically many measurement…

Quantum Physics · Physics 2021-08-09 Jason Saunders , Jean-Francois Van Huele

Measurements in the quantum domain can exceed classical notions. This concerns fundamental questions about the nature of the measurement process itself, as well as applications, such as their function as building blocks of quantum…

Quantum Physics · Physics 2023-02-02 Jan Sperling , Ilaria Gianani , Marco Barbieri , Elizabeth Agudelo

We report on experimental studies on entanglement quantification and verification based on uncertainty relations for systems consisting of two qubits. The new proposed measure is shown to be invariant under local unitary transformations, by…

Quantum Physics · Physics 2007-05-23 Zhi-Wei Wang , Yun-Feng Huang , Xi-Feng Ren , Yong-Sheng Zhang , Guang-Can Guo

Quantum metrology employs entanglement to enhance measurement precision. The focus and progress so far have primarily centered on estimating a single parameter. In diverse application scenarios, the estimation of more than one single…

Quantum Physics · Physics 2025-07-31 Jiahao Cao , Xinwei Li , Tianwei Mao , Wenxin Xu , Li You

Entanglement and uncertainty relation are two focuses of quantum theory. We relate entanglement sharing to the entropic uncertainty relation in a $(d\times d)$-dimensional system via weak measurements with different pointers. We consider…

Quantum Physics · Physics 2023-07-25 Ming-Liang Hu , Heng Fan

Quantum entanglement is a key ingredient for quantum information processing with capabilities beyond that of classical computation. We study the generation and role of entanglement in the dynamics of spin-1/2 models, both for the design of…

Quantum Physics · Physics 2024-06-11 Anupam Mitra

The uncertainty principle, which bounds the uncertainties involved in obtaining precise outcomes for two complementary variables defining a quantum particle, is a crucial aspect in quantum mechanics. Recently, the uncertainty principle in…

Quantum Physics · Physics 2012-04-24 Chuan-Feng Li , Jin-Shi Xu , Xiao-Ye Xu , Ke Li , Guang-Can Guo

Entanglement is considered to be one of the most profound features of quantum mechanics. An entangled state of a system consisting of two subsystems cannot be described as a product of the quantum states of the two subsystems. In this sense…

Quantum Physics · Physics 2009-11-07 Brian Julsgaard , Alexander Kozhekin , Eugene S. Polzik

An exactly solvable model for a quantum measurement is discussed, that integrates quantum measurements with classical measurements. The z-component of a spin-1/2 test spin is measured with an apparatus, that itself consists of magnet of N…

Mesoscale and Nanoscale Physics · Physics 2007-05-23 A. E. Allahverdyan , R. Balian , Th. M. Nieuwenhuizen

Measurement-based entanglement is a method for entangling quantum systems through the state projection that accompanies a parity measurement. We derive a stochastic master equation describing measurement-based entanglement of a pair of…

Quantum Physics · Physics 2024-07-17 Remy L. Delva , Jonas Mielke , Guido Burkard , Jason R. Petta

Quantum circuit dynamics with local projective measurements can realize a rich spectrum of entangled states of quantum matter. Motivated by the physics of the Kitaev quantum spin liquid [1], we study quantum circuit dynamics in…

Strongly Correlated Electrons · Physics 2022-07-08 Ali Lavasani , Zhu-Xi Luo , Sagar Vijay

We propose a new approach to the problem of defining the degree of entanglement between two particles in a pure state with Hilbert spaces of arbitrary finite dimensions. The central idea is that entanglement gives rise to correlations…

Quantum Physics · Physics 2007-05-23 Markus A. Cirone