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Quantum correlations are at the core of the power of quantum information and are necessary to reach a quantum computational advantage. In the context of continuous-variable quantum systems, another necessary ressource for quantum advantages…

Quantum Physics · Physics 2024-07-26 Carlos E. Lopetegui , Mathieu Isoard , Nicolas Treps , Mattia Walschaers

Quantum-enhanced metrology surpasses classical metrology by improving estimation precision scaling with a resource $N$ (e.g., particle number or energy) from $1/\sqrt{N}$ to $1/N$. Through the use of nonlinear effects, Roy and…

Quantum Physics · Physics 2025-04-07 Noah Lordi , John Drew Wilson , Murray J. Holland , Joshua Combes

A model of noise reduction (NR) for signal processing is introduced. Each noise source puts a symmetric constraint on the space of the signal vector within a tolerable overlap. When the number of noise sources increases, sequences of…

Disordered Systems and Neural Networks · Physics 2007-05-23 J. van Mourik , K. Y. Michael Wong , D. Bolle'

There are four reasons why our present knowledge and understanding of quantum mechanics could be regarded as incomplete. Firstly, the principle of linear superposition has not been experimentally tested for position eigenstates of objects…

Quantum Physics · Physics 2010-06-21 Kinjalk Lochan , T. P. Singh

Coherent errors, and especially those that occur in correlation among a set of qubits, are detrimental for large-scale quantum computing. Correlations in noise can occur as a result of spatial and temporal configurations of instructions…

Object detection and range finding using a weak light source is vulnerable to jamming and spoofing attacks by an intruder. Quantum illumination with nonsimultaneous, phase-insensitive coincidence measurements can provide jamming resilience…

Quantum Physics · Physics 2025-10-29 Richard J. Murchie , John Jeffers

Quantum-dense metrology (QDM) constitutes a special case of quantum metrology in which two orthogonal phase space projections of a signal are simultaneously sensed beyond the shot noise limit. Previously it was shown that the additional…

Quantum Physics · Physics 2016-11-02 Melanie Ast , Sebastian Steinlechner , Roman Schnabel

Maximizing the computational utility of near-term quantum processors requires predictive noise models that inform robust, noise-aware compilation and error mitigation. Conventional models often fail to capture the complex error dynamics of…

Quantum Physics · Physics 2026-03-17 Yanjun Ji , Marco Roth , David A. Kreplin , Ilia Polian , Frank K. Wilhelm

Quantum computers are known for their potential to achieve up-to-exponential speedup compared to classical computers for certain problems. To exploit the advantages of quantum computers, we propose quantum algorithms for linear stochastic…

Quantum Physics · Physics 2025-06-26 Shi Jin , Nana Liu , Wei Wei

We address the metrological problem of estimating collective stochastic properties imprinted on a network of quantum sensors. Canonical examples include center-of-mass quadrature fluctuations in a system of bosonic modes and correlated…

Quantum Physics · Physics 2026-02-27 Anthony J. Brady , Yu-Xin Wang , Victor V. Albert , Alexey V. Gorshkov , Quntao Zhuang

Nonclassical states are essential for optics-based quantum information processing, but their fragility limits their utility for practical scenarios in which loss and noise inevitably degrade, if not destroy, nonclassicality. Exploiting…

Quantum Physics · Physics 2015-03-25 Zheshen Zhang , Sara Mouradian , Franco N. C. Wong , Jeffrey H. Shapiro

Despite the unquestionable empirical success of quantum theory, witnessed by the recent uprising of quantum technologies, the debate on how to reconcile the theory with the macroscopic classical world is still open. Spontaneous collapse…

Quantum Physics · Physics 2020-09-04 A. Vinante , M. Carlesso , A. Bassi , A. Chiasera , S. Varas , P. Falferi , B. Margesin , R. Mezzena , H. Ulbricht

Genuine multipartite entanglement is arguably the most valuable form of entanglement in the multipartite case, with applications, for instance, in quantum metrology. In order to detect that form of entanglement in multipartite quantum…

Quantum Physics · Physics 2026-04-07 Jakub Szczepaniak , Owidiusz Makuta , Remigiusz Augusiak

We introduce a technique for the suppression of state-dependent and correlated measurement errors, which are commonly observed on modern superconducting quantum devices. Our method leverages previous results, establishing that correlated…

Quantum Physics · Physics 2022-12-22 Alan Robertson , Shuaiwen Leon Song

Nonlinear quantum dynamics is often invoked in models trying to bridge the gap between the quantum micro-world and the classical macro-world. Such endeavors, however, encounter challenges at the nexus with relativity. In 1989 Nicolas Gisin…

Quantum Physics · Physics 2024-12-31 Marta Emilia Bielińska , Michał Eckstein , Paweł Horodecki

Entanglement is a central concept in quantum information and a key resource for many quantum protocols. In this work we propose and analyze a class of entanglement witnesses that detect the presence of entanglement in subsystems of…

Quantum Physics · Physics 2020-01-22 David Amaro , Markus Müller

Quantum supremacy poses that a realistic quantum computer can perform a calculation that classical computers cannot in any reasonable amount of time. It has become a topic of significant research interest since the birth of the field, and…

Quantum Physics · Physics 2023-01-10 Kabgyun Jeong

We propose a theoretical scheme to enhance the signal-to-noise ratio in ultrasensitive detection with the help of quantum correlation. By introducing the auxiliary oscillator and treated as an added probe for weak field detection, the…

Quantum Physics · Physics 2019-06-12 Wen-Zhao Zhang , Li-Bo Chen , Jiong Cheng , Yun-Feng Jiang

Analog models of quantum information processing, such as adiabatic quantum computation and analog quantum simulation, require the ability to subject a system to precisely specified Hamiltonians. Unfortunately, the hardware used to implement…

Quantum Physics · Physics 2014-02-25 Kevin C. Young , Robin Blume-Kohout , Daniel A. Lidar

Quantum illumination consists in shining quantum light on a target region immersed in a bright thermal bath, with the aim of detecting the presence of a possible low-reflective object. If the signal is entangled with the receiver, then a…

Quantum Physics · Physics 2017-02-28 M. Sanz , U. Las Heras , J. J. Garcia-Ripoll , E. Solano , R. Di Candia