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Related papers: Parity-Enhanced Quantum Optimal Measurements

200 papers

The simultaneous multi-parameter estimation problem using a class of multi-mode entangled states is investigated in this paper. Specifically, the problem of optical phase imaging is considered and the quantum probe is taken to be a balanced…

Quantum Physics · Physics 2017-03-29 Lu Zhang , Kam Wai Clifford Chan

Bounds on the ultimate precision attainable in the estimation of a parameter in Gaussian quantum metrology are obtained when the average number of bosonic probes is fixed. We identify the optimal input probe state among generic (mixed in…

Quantum Physics · Physics 2019-03-21 Teruo Matsubara , Paolo Facchi , Vittorio Giovannetti , Kazuya Yuasa

Quantum effects like entanglement and coherent amplification can be used to drastically enhance the accuracy of quantum parameter estimation beyond classical limits. However, challenges such as decoherence and time-dependent errors hinder…

Quantum Physics · Physics 2025-02-18 Yulong Dong , Jonathan A. Gross , Murphy Yuezhen Niu

The incompatibility of the measurements constraints the achievable precisions in multi-parameter quantum estimation. Understanding the tradeoff induced by such incompatibility is a central topic in quantum metrology. Here we provide an…

Quantum Physics · Physics 2022-06-28 Hongzhen Chen , Yu Chen , Haidong Yuan

Quantum scale estimation, as introduced and explored here, establishes the most precise framework for the estimation of scale parameters that is allowed by the laws of quantum mechanics. This addresses an important gap in quantum metrology,…

Quantum Physics · Physics 2022-11-18 Jesús Rubio

Recently, the Hilbert-Schmidt speed, as a special class of quantum statistical speed, has been reported to improve the interferometric phase in single-parameter quantum estimation. Here, we test this concept in the multiparameter scenario…

Quantum Physics · Physics 2023-10-27 Nour-Eddine Abouelkhir , Abdallah Slaoui , Hanane El Hadfi , Rachid Ahl Laamara

The accuracy of quantum measurements can be effectively improved by using both photon-added non-Gaussian operations and Kerr nonlinear phase shifters. Here, we employ coherent state mixed photon-added squeezed vacuum state as input into a…

Quantum Physics · Physics 2025-05-23 Zekun Zhao , Qingqian Kang , Shoukang Chang , Teng Zhao , Cunjin Liu , Xin Su , Liyun Hu

In quantum multiparameter estimation, multiple to-be-estimated parameters are encoded in a quantum dynamics system by a unitary evolution. As the parameters vary, the system may undergo a topological phase transition (TPT). In this paper,…

Quantum Physics · Physics 2024-02-13 Yu Yang , Haidong Yuan , Fuli Li

We address parameter estimation in two-level systems exhibiting level anti-crossing and prove that universally optimal strategies for parameter estimation may be designed, that is, we may find a parameter independent measurement scheme…

Quantum Physics · Physics 2018-01-24 Luca Ghirardi , Ilaria Siloi , Paolo Bordone , Filippo Troiani , Matteo G. A. Paris

We suggest an interferometric scheme assisted by squeezing and linear feedback to realize the whole class of field-quadrature quantum nondemolition measurements, from Von Neumann projective measurement to fully non-destructive…

Quantum Physics · Physics 2009-11-07 Matteo G. A. Paris

Precision metrology and quantum measurement often demand matter be prepared in well defined quantum states for both internal and external degrees of freedom. Laser-cooled neutral atoms localized in a deeply confining optical potential…

Quantum Physics · Physics 2009-11-13 Jun Ye , H. J. Kimble , Hidetoshi Katori

Many protocols require precise rotation measurement. Here we present a general class of states that surpass the shot noise limit for measuring rotation around arbitrary axes. We then derive a quantum Cram\'er-Rao bound for simultaneously…

Quantum Physics · Physics 2019-03-20 Aaron Z. Goldberg , Daniel F. V. James

Quantum phase estimation is one of the key algorithms in the field of quantum computing, but up until now, only approximate expressions have been derived for the probability of error. We revisit these derivations, and find that by ensuring…

Quantum Physics · Physics 2012-02-13 James M. Chappell , Max A. Lohe , Lorenz von Smekal , Azhar Iqbal , Derek Abbott

In Quantum Non Demolition measurements, the sequence of observations is distributed as a mixture of multinomial random variables. Parameters of the dynamics are naturally encoded into this family of distributions. We show the local…

Quantum Physics · Physics 2017-07-20 Tristan Benoist , F Gamboa , C Pellegrini

Seeking the available precision limit of unknown parameters is a significant task in quantum parameter estimation. One often resorts to the widely utilized quantum Cramer-Rao bound (QCRB) based on unbiased estimators to finish this task.…

Quantum Physics · Physics 2023-09-12 Shoukang Chang , Wei Ye , Xuan Rao , Huan Zhang , Liqing Huang , Mengmeng Luo , Yuetao Chen , Qiang Ma , Shaoyan Gao

Quantum metrology offers the potential to surpass its classical counterpart, pushing the boundaries of measurement precision toward the ultimate Heisenberg limit. This enhanced precision is normally attained by utilizing large squeezed…

We give a bound to the precision in the estimation of a parameter in terms of the expectation value of an observable. It is an extension of the Cramer-Rao inequality and of the Heisenberg uncertainty relation, where the estimation precision…

Quantum Physics · Physics 2012-07-11 Vittorio Giovannetti , Seth Lloyd , Lorenzo Maccone

Quantum multiparameter estimation offers a framework for the simultaneous estimation of multiple parameters, pertaining to possibly noncommutating observables. While the optimal probe for estimating a single unitary phase is well understood…

Quantum Physics · Physics 2025-07-08 Ritopriyo Pal , Priya Ghosh , Ahana Ghoshal , Ujjwal Sen

We explore precision in a measurement process incorporating pure probe states, unitary dynamics and complete measurements via a simple formalism. The concept of `information complement' is introduced. It undermines measurement precision and…

Quantum Physics · Physics 2010-02-17 Gabriel A. Durkin

Quantum technologies exploit entanglement to revolutionize computing, measurements, and communications. This has stimulated the research in different areas of physics to engineer and manipulate fragile many-particle entangled states.…

Quantum Physics · Physics 2018-11-13 Luca Pezzè , Augusto Smerzi , Markus K. Oberthaler , Roman Schmied , Philipp Treutlein