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Related papers: Nonlocality, steering and quantum state tomography…

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Quantum theory allows for nonlocality without entanglement. Notably, there exist bipartite quantum measurements consisting of only product eigenstates, yet they cannot be implemented via local quantum operations and classical communication.…

Quantum Physics · Physics 2023-07-12 Ivan Šupić , Nicolas Brunner

Quantum steering is a recently-defined form of quantum correlation which lies at the heart of quantum mechanics. In difference from other types of quantum correlations, quantum steering is inherently asymmetric, which implies that it could…

Quantum Physics · Physics 2022-02-25 Qiang Zeng , Jiangwei Shang , H. Chau Nguyen , Xiangdong Zhang

Quantum steering---a strong correlation to be verified even when one party or its measuring device is fully untrusted---not only provides a profound insight into quantum physics but also offers a crucial basis for practical applications.…

Quantum Physics · Physics 2016-07-18 Se-Wan Ji , Jaehak Lee , Jiyong Park , Hyunchul Nha

Einstein-Podolsky-Rosen steering is a kind of powerful nonlocal quantum resource in quantum information processing such as quantum cryptography and quantum communication. Many criteria have been proposed in the past few years to detect…

Quantum Physics · Physics 2022-09-16 Zhihua Chen , Shao-Ming Fei

Entanglement allows for the nonlocality of quantum theory, which is the resource behind device-independent quantum information protocols. However, not all entangled quantum states display nonlocality, and a central question is to determine…

Quantum Physics · Physics 2016-11-09 Daniel Cavalcanti , Leonardo Guerini , Rafael Rabelo , Paul Skrzypczyk

Measurements with randomly chosen settings determine many important properties of quantum states without the need for a shared reference frame or calibration. They naturally emerge in the context of quantum communication and quantum…

Quantum steering is an asymmetric form of quantum nonlocality where one can detect whether a measurement on one system can steer or change another distant system. It is well-known that there are quantum states that are entangled but…

Quantum Physics · Physics 2026-04-03 Shubhayan Sarkar

In contrast with classical physics, in quantum physics some sets of measurements are incompatible in the sense that they can not be performed simultaneously. Among other applications, incompatibility allows for contextuality and Bell…

Quantum steering is a fundamental quantum correlation that plays a pivotal role in quantum technologies, but its verification crucially relies on precise measurements -- an assumption often undermined by practical imperfections. Here, we…

Quantum Physics · Physics 2025-11-12 Zeyang Lu , Chan Li , Gang Wang , Zhu Cao

Quantum steering is observed when performing appropriate local measurements on an entangled state. Here we discuss the possibility of simulating classically this effect, using classical communication instead of entanglement. We show that…

Quantum Physics · Physics 2016-07-14 Ana Belén Sainz , Leandro Aolita , Nicolas Brunner , Rodrigo Gallego , Paul Skrzypczyk

Opto- and electromechanical systems offer an effective platform to test quantum theory and its predictions at macroscopic scales. To date, all experiments presuppose the validity of quantum mechanics, but could in principle be described by…

Quantum Physics · Physics 2016-02-24 Sebastian G. Hofer , Konrad W. Lehnert , Klemens Hammerer

Einstein-Podolsky-Rosen (EPR) steering and Bell nonlocality illustrate two different kinds of correlations predicted by quantum mechanics. They not only motivate the exploration of the foundation of quantum mechanics, but also serve as…

Quantum Physics · Physics 2023-09-29 Wei-Hao Huang , Shih-Hsuan Chen , Chun-Hao Chang , Tzu-Liang Hsu , Kuan-Jou Wang , Che-Ming Li

The future of quantum communication relies on quantum networks composed by observers sharing multipartite quantum states. The certification of multipartite entanglement will be crucial to the usefulness of these networks. In many real…

Quantum Physics · Physics 2016-02-16 D. Cavalcanti , P. Skrzypczyk , G. H. Aguilar , R. V. Nery , P. H. Souto Ribeiro , S. P. Walborn

Tomographic measurements are the standard tool for characterizing quantum states, yet they are usually regarded only as means for state reconstruction or fidelity measurement. Here, we show that the same Pauli-basis measurements (X, Y, Z)…

Quantum Physics · Physics 2026-05-13 Pawel Cieslinski , Lukas Knips , Harald Weinfurter , Wieslaw Laskowski

Quantum inseparabilities can be classified into three inequivalent forms: entanglement, Einstein-Podolsky-Rosen (EPR) steering, and Bell's nonlocality. Bell-nonlocal states form a strict subset of EPR steerable states which also form a…

Quantum Physics · Physics 2019-05-22 Debarshi Das , Souradeep Sasmal , Sovik Roy

There have been studies on formation of quantum-nonlocal states in spatially separate two cavities. We suggest a nonlocal test for the field prepared in the two cavities. We couple classical driving fields with the cavities where a nonlocal…

Quantum Physics · Physics 2009-11-06 M. S. Kim , Jinhyoung Lee

The celebrated Einstein-Podolsky-Rosen quantum steering has a complex structure in the multipartite scenario. We show that a naively defined criterion for multipartite steering allows, like in Bell nonlocality, for a contradictory effect…

Quantum Physics · Physics 2021-05-07 M. M. Taddei , T. L. Silva , R. V. Nery , G. H. Aguilar , S. P. Walborn , L. Aolita

We experimentally demonstrate the nonlocal reversal of a partial-collapse quantum measurement on two-photon entangled state. Both the partial measurement and the reversal operation are implemented in linear optics with two displaced Sagnac…

Quantum Physics · Physics 2015-05-20 Xiao-Ye Xu , Jin-Shi Xu , Chuan-Feng Li , Yang Zou , Guang-Can Guo

Loophole-free quantum nonlocality often demands experiments with high complexity (defined by all parties' settings and outcomes) and multiple efficient detectors. Here, we identify the fundamental efficiency and complexity thresholds for…

Quantum randomness can be certified from probabilistic behaviors demonstrating Bell nonlocality or Einstein-Podolsky-Rosen steering, leveraging outcomes from uncharacterized devices. However, such nonlocal correlations are not always…

Quantum Physics · Physics 2025-10-21 Yi Li , Yu Xiang , Jordi Tura , Qiongyi He