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Related papers: Quantum entanglement from random measurements

200 papers

We consider statistical methods based on finite samples of locally randomized measurements in order to certify different degrees of multiparticle entanglement in intermediate-scale quantum systems. We first introduce hierarchies of…

Quantum Physics · Physics 2023-06-08 Andreas Ketterer , Satoya Imai , Nikolai Wyderka , Otfried Gühne

Entanglement constitutes a key characteristic feature of quantum matter. Its detection, however, still faces major challenges. In this letter, we formulate a framework for probing entanglement based on machine learning techniques. The…

Quantum Physics · Physics 2021-08-18 Jun Yong Khoo , Markus Heyl

Contrary to Bell scenario, quantum nonlocality can be exploited even when all the parties do not have freedom to select inputs randomly. Such manifestation of nonlocality is possible in networks involving independent sources. One can…

Quantum Physics · Physics 2020-04-20 Kaushiki Mukherjee , Biswajit Paul , Arup Roy

Entanglement, including ``quantum entanglement,'' is a consequence of correlation between objects. When the objects are subunits of pairs which in turn are members of an ensemble described by a wave function, a correlation among the…

Quantum Physics · Physics 2009-11-07 A. F. Kracklauer

Quantum mechanics allows systems to be entangled with each other, which results in stronger than classical correlations. Many methods of identifying entanglement have been proposed over years, most of which are based on violating some…

Quantum Physics · Physics 2014-12-31 Ramij Rahaman , Marcin Wieśniak , Marek Żukowski

Entanglement is at the heart of most quantum information tasks, and therefore considerable effort has been made to find methods of deciding the entanglement content of a given bipartite quantum state. Here, we prove a fundamental limitation…

Quantum Physics · Physics 2016-06-15 Claudio Carmeli , Teiko Heinosaari , Antti Karlsson , Jussi Schultz , Alessandro Toigo

Entanglement--one of the most delicate phenomena in nature--is an essential resource for quantum information applications. Large entangled cluster states have been predicted to enable universal quantum computation, with the required single-…

Entangled many-body states are an essential resource for quantum computing and interferometry. Determining the type of entanglement present in a system usually requires access to an exponential number of parameters. We show that in the case…

Quantum Physics · Physics 2014-11-17 Michael Walter , Brent Doran , David Gross , Matthias Christandl

Tremendous progress has been realized in quantum optics for engineering and detecting the quantum properties of light. Today, photon pairs are routinely created in entangled states. Entanglement is revealed using single-photon detectors in…

Quantum Physics · Physics 2016-05-16 Valentina Caprara Vivoli , Pavel Sekatski , Nicolas Sangouard

Measurement interaction between a measured object and a measuring instrument, if both are initially in a pure state, produces a (final) bipartite entangled state vector. The quasi-classical part of the correlations in it is connected with…

Quantum Physics · Physics 2007-05-23 Fedor Herbut

We present a way of identifying all kinds of entanglement for three-qubit pure states in terms of the expectation values of Pauli operators. The necessary and sufficient conditions to classify the fully separable, biseparable, and genuine…

Quantum Physics · Physics 2015-06-12 Ming-Jing Zhao , Ting-Gui Zhang , Xianqing Li-Jost , Shao-Ming Fei

Quantum entanglement is an important resource in many modern technologies, like quantum computation or quantum communication and information processing. Therefore, most interest is given to detect and quantify entangled states. Entanglement…

Quantum Physics · Physics 2026-05-12 Katarzyna Siudzińska

We experimentally detect entanglement in modular position and momentum variables of photon pairs which have passed through $D$-slit apertures. We first employ an entanglement criteria recently proposed in [Phys. Rev. Lett. {\bf 106}, 210501…

Quantum Physics · Physics 2015-06-11 M. A. D. Carvalho , J. Ferraz , G. F. Borges , P. L. de Assis , S. Pádua , S. P. Walborn

Entanglement is an important resource that allows quantum technologies to go beyond the classically possible. There are many ways quantum systems can be entangled, ranging from the archetypal two-qubit case to more exotic scenarios of…

Quantum Physics · Physics 2019-06-27 Nicolai Friis , Giuseppe Vitagliano , Mehul Malik , Marcus Huber

Quantum theory predicts that entanglement can also persist in macroscopic physical systems, albeit difficulties to demonstrate it experimentally remain. Recently, significant progress has been achieved and genuine entanglement between up to…

While entanglement plays an important role in characterizing quantum many-body systems, it is hardly possible to directly access many-body entanglement in real experiments. In this paper, we study how bipartite entanglement of many-body…

Quantum Physics · Physics 2018-07-11 Chae-Yeun Park , Jaeyoon Cho

We present a new technique to reduce the expected number of measurements to declare an unknown quantum state as entangled. Our method is based on the geometric criterion and so requires only local Pauli measurements. Using concentration of…

Quantum Physics · Physics 2017-09-13 Bingjie Wang , Stephen Brierley

Non-classical correlations between measurement results make entanglement the essence of quantum physics and the main resource for quantum information applications. Surprisingly, there are $n$-particle states which do not exhibit $n$-partite…

The entanglement detection via local measurements can be experimentally implemented. Based on mutually unbiased measurements and general symmetric informationally complete positive-operator-valued measures, we present separability criteria…

Quantum Physics · Physics 2018-03-30 Shu-Qian Shen , Ming Li , Xianqing Li-Jost , Shao-Ming Fei

Projective measurements are a powerful tool for manipulating quantum states. In particular, a set of qubits can be entangled by measurement of a joint property such as qubit parity. These joint measurements do not require a direct…