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Multi-dimensional entangled states have been proven to be more powerful in some quantum information process. In this paper, down-converted photons from spontaneous parametric down conversion(SPDC) are used to engineer multi-dimensional…

Quantum Physics · Physics 2015-06-26 Xi-Feng Ren , Guo-Ping Guo , Jian Li , Chuan-Feng Li , Guang-Can Guo

We generalize the recently proposed Greenberger-Horne-Zeilinger (GHZ) tripartite protocol [A. Galiautdinov, J. M. Martinis, Phys. Rev. A 78, 010305(R) (2008)] to fully connected networks of weakly coupled qubits interacting by way of…

Quantum Physics · Physics 2015-05-13 Andrei Galiautdinov , Mark W. Coffey , Ron Deiotte

Bipartite and multipartite entangled states are basic ingredients for constructing quantum networks and their accurate verification is crucial to the functioning of the networks, especially for untrusted networks. Here we propose a simple…

Quantum Physics · Physics 2021-12-28 Yun-Guang Han , Zihao Li , Yukun Wang , Huangjun Zhu

We propose and demonstrate experimentally a scheme to create entangled history states of the Greenberger-Horne-Zeilinger (GHZ) type. In our experiment, the polarization states of a single photon at three different times are prepared as a…

Quantum Physics · Physics 2017-12-06 Jordan Cotler , Lu-Ming Duan , Pan-Yu Hou , Frank Wilczek , Da Xu , Zhang-Qi Yin , Chong Zu

We provide evidence that three-party entanglement signals in holography obey a relation that is not satisfied by generalized Greenberger-Horne-Zeilinger (GHZ) states. Using proposed holographic duals for these entanglement signals, we…

High Energy Physics - Theory · Physics 2026-03-18 Vijay Balasubramanian , Monica Jinwoo Kang , Charlie Cummings , Chitraang Murdia , Simon F. Ross

The generation of quantum entangled states of many particles is a central goal of quantum information science. Characterizing such states is a complex task that demands exponentially large resources as particles are being added. Previously,…

Quantum Physics · Physics 2017-12-12 E. Megidish , A. Halevy , Y. Pilnyak , A. Slapa , H. S. Eisenberg

Accurately characterizing multipartite entangled states is a critical challenge in quantum information processing. In this work, we focus on applying compressed sensing techniques to efficiently estimate the fidelity of…

Quantum Physics · Physics 2026-05-01 Farrokh Labib , David Nicholaeff , Vincent Russo , William J. Zeng

Despite the fundamental importance of quantum entanglement in many-body systems, our understanding is mostly limited to bipartite situations. Indeed, even defining appropriate notions of multipartite entanglement is a significant challenge…

Quantum Physics · Physics 2021-01-15 Sepehr Nezami , Michael Walter

Encoding high-dimensional quantum information into single photons can provide a variety of benefits for quantum technologies, such as improved noise resilience. However, the efficient generation of on-demand, high-dimensional entanglement…

Multiphoton entanglement, as a quantum resource, plays an essential role in linear optical quantum information processing. Krenn et al. (Phys. Rev. Lett. 118, 080401 2017) proposed an innovative scheme that generating entanglement by path…

Quantum Physics · Physics 2020-04-09 Tianfeng Feng , Xiaoqian Zhang , Yuling Tian , Qin Feng

Measurement based quantum computing is preformed by adding non-Clifford measurements to a prepared stabilizer states. Entangling gates like CZ are likely to have lower fidelities due to the nature of interacting qubits, so when preparing a…

Quantum Physics · Physics 2025-07-29 James Davies , Andrew Jena

Generating large multiphoton entangled states is of main interest due to enabling universal photonic quantum computing and all-optical quantum repeater nodes. These applications exploit measurement-based quantum computation using cluster…

Quantum Physics · Physics 2025-07-22 H. Cao , L. M. Hansen , F. Giorgino , L. Carosini , P. Zahalka , F. Zilk , J. C. Loredo , P. Walther

Graph states form a rich class of entangled states that exhibit important aspects of multi-partite entanglement. At the same time, they can be described by a number of parameters that grows only moderately with the system size. They have a…

Quantum Physics · Physics 2007-05-23 M. Hein , W. Dür , J. Eisert , R. Raussendorf , M. Van den Nest , H. -J. Briegel

The Greenberger-Horne-Zeilinger (GHZ) state is a key resource for quantum information processing and quantum metrology. The atomic GHZ state can be generated by one-axis twisting (OAT) interaction $H_{\mathrm{OAT}}=\chi J_{z}^{2}$ with…

Quantum Physics · Physics 2024-03-14 Xuanchen Zhang , Zhiyao Hu , Yong-Chun Liu

We introduce a single real-valued functional $I(\vec{n}_1,\vec{n}_2)$, built from four three-qubit correlation expectation values, that turns the Greenberger--Horne--Zeilinger (GHZ) algebraic paradox into a \emph{quantitative} witness of…

Quantum Physics · Physics 2026-05-05 Shengjun Wu , Kaichen Zhong , Jeffery Wu

The concatenated Greenberger-Horne-Zeiglinger (C-GHZ) state which is a new type of logic-qubit entanglement has attracted a lot of attentions recently. We present a feasible entanglement concentration protocol (ECP) for logic-qubit…

Quantum Physics · Physics 2016-02-09 Yu-Bo Sheng , Chang-Cheng Qu , Lan Zhou

Systems of four nonbinary particles, each having three or more internal states, exhibit maximally entangled states that are inaccessible to four qubits. This breaks the pattern of two- and three-particle systems, in which the existing graph…

Quantum Physics · Physics 2015-06-23 Mario Gaeta , Andrei Klimov , Jay Lawrence

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

Cluster states are multi-particle entangled states with special entanglement properties particularly suitable for quantum computation. It has been shown that cluster states can exhibit Greenberger-Horne-Zeilinger (GHZ)-type non-locality…

Quantum Physics · Physics 2009-11-13 X. -Q. Zhou , C. -Y. Lu , W. -B. Gao , J. Zhang , Z. -B. Chen , T. Yang , J. -W. Pan

Mutually entangled multi-photon states are at the heart of all-optical quantum technologies. While impressive progresses have been reported in the generation of such quantum light states using free space apparatus, high-fidelity high-rate…