English
Related papers

Related papers: A Greenberger-Horne-Zeilinger experiment for mixed…

200 papers

High-dimensional quantum entanglement characterizes the entanglement of quantum systems within a larger Hilbert space, introducing more intricate and complex correlations among the entangled particles' states. The high-dimensional…

Quantum Physics · Physics 2024-03-13 Yue Zhao , Yu-Qing Yang , Weibin Li , Xiao-Qiang Shao

This paper surveys our recent research on quantum information processing by nuclear magnetic resonance (NMR) spectroscopy. We begin with a geometric introduction to the NMR of an ensemble of indistinguishable spins, and then show how this…

Quantum Physics · Physics 2007-05-23 T. F. Havel , S. S. Somaroo , C. -H. Tseng , D. G. Cory

We present a generalized Greenberger-Horne-Zeilinger (GHZ) theorem, which involves more than two local measurement settings for some parties, and cannot be reduced to one with less settings. Our results hold for an odd number of parties. We…

We generalize Greenberger-Horne-Zeilinger (GHZ) nonlocality to every even-dimensional and odd-partite system. For the purpose we employ concurrent observables that are incompatible and nevertheless have a common eigenstate. It is remarkable…

Quantum Physics · Physics 2007-05-23 Jinhyoung Lee , Seung-Woo Lee , M. S. Kim

We consider an entangled two-particle state that is produced from two independent down-conversion sources by the process of "entanglement-swapping", so that the particles have never met. We prove a Greenberger-Horne-Zeilinger (GHZ) type…

Quantum Physics · Physics 2008-08-01 Daniel M. Greenberger , Michael Horne , Anton Zeilinger

The Clauser-Horne-Shimony-Holt inequality was originally proposed as a Bell inequality to detect nonlocality in bipartite systems. However, it can also be used to certify the nonlocality of multipartite quantum states. We apply this to…

Quantum Physics · Physics 2014-06-02 Rafael Chaves , Antonio Acín , Leandro Aolita , Daniel Cavalcanti

Using simple quantum analysis we describe the correlations of Greenberger-Horne-Zeilinger (GHZ) states by the use of Hilbert-Schmidt (HS) representation. Our conclusion is that while these states disprove local-realism they do not prove any…

Quantum Physics · Physics 2009-11-10 Y. Ben-Aryeh

Quantum mechanics predicts a number of at first sight counterintuitive phenomena. It is therefore a question whether our intuition is the best way to find new experiments. Here we report the development of the computer algorithm Melvin…

Quantum Physics · Physics 2016-03-07 Mario Krenn , Mehul Malik , Robert Fickler , Radek Lapkiewicz , Anton Zeilinger

NMR is emerging as a valuable testbed for the investigation of foundational questions in quantum mechanics. The present paper outlines the preparation of a class of mixed states, called pseudo-pure states, that emulate pure quantum states…

It is well known that Bell inequality supporting the local realism can be violated in quantum mechanics. Numerous tests of such a violation have been demonstrated with bipartite entanglements. Using spectral jointmeasurements of the qubits,…

Quantum Physics · Physics 2015-05-27 J. S. Huang , C. H. Oh , L. F. Wei

We propose a complete architecture for deterministic generation of entangled multiphoton states. Our approach utilizes periodic driving of a quantum-dot emitter and an efficient light-matter interface enabled by a photonic crystal…

High-quality entangled photon pairs generated via spontaneous parametric down-conversion have made great contributions to the modern quantum information science and the fundamental tests of quantum mechanics. However, the quality of the…

Quantum Physics · Physics 2017-02-15 Chao Zhang , Yun-Feng Huang , Chengjie Zhang , Jian Wang , Bi-Heng Liu , Chuan-Feng Li , Guang-Can Guo

The Wigner rotation of quantum particles with spin is one of the fascinating consequences of interplay between special relativity and quantum mechanics. In this paper we show that a direct experimental verification of Wigner's rotation is…

Quantum Physics · Physics 2025-04-03 Veiko Palge , Jacob Dunningham , Yuji Hasegawa , Christian Pfeifer

Quantum entangled states have shown distinguished features beyond any classical state. Many methods like quantum state tomography have been presented to verify entanglement. In this work, we aim to identify unknown entanglements with…

Quantum Physics · Physics 2021-11-29 Ming-Xing Luo , Shao-Ming Fei , Jing-Ling Chen

We study the stability of superpositions of macroscopically distinct quantum states under decoherence. We introduce a class of quantum states with entanglement features similar to Greenberger-Horne-Zeilinger (GHZ) states, but with an…

Quantum Physics · Physics 2011-03-18 F. Fröwis , W. Dür

Multipartite entanglement is one of the core concepts in quantum information science with broad applications that span from condensed matter physics to quantum physics foundations tests. Although its most studied and tested forms encompass…

Quantum Physics · Physics 2022-02-25 Alba Cervera-Lierta , Mario Krenn , Alán Aspuru-Guzik , Alexey Galda

Quantum nonlocality of several four-qubit states is investigated by constructing a new Bell inequality. These include the Greenberger-Zeilinger-Horne (GHZ) state, W state, cluster state, and the state $|\chi>$ that has been recently…

Quantum Physics · Physics 2013-05-29 Chunfeng Wu , Ye Yeo , L. C. Kwek , C. H. Oh

We present a scheme for the multi-electron Greenberger-Horne-Zeilinger (GHZ) state analyzer, resorting to an interface between the polarization of a probe photon and the spin of an electron in a quantum dot embedded in a microcavity. All…

Quantum Physics · Physics 2012-09-24 Hai-Rui Wei , Bao-Cang Ren , Mei Zhang , Tao Li , Fu-Guo Deng

Quantifying mixed-state entanglement in many-body systems has been a formidable task. In this work, we quantify the entanglement of states in unresolvable spin ensembles, which are inherently mixed. By exploiting their permutationally…

Quantum Physics · Physics 2025-11-05 Tzu-Wei Kuo , Hoi-Kwan Lau

In this review, we describe the potentialities offered by the nuclear magnetic resonance (NMR) technique to explore at a microscopic level new quantum states of condensed matter induced by high magnetic fields. We focus on experiments…

Strongly Correlated Electrons · Physics 2017-11-30 Claude Berthier , Mladen Horvatić , Marc-Henri Julien , Hadrien Mayaffre , Steffen Krämer