English
Related papers

Related papers: Machine-Learning-Derived Entanglement Witnesses

200 papers

We propose a method to witness entanglement between two continuous-variable systems in a Gaussian state. Its key ingredient is a local lossy state transfer from the original spatially separated systems onto two spatially separated qubits.…

Quantum Physics · Physics 2021-03-17 Waldemar Klobus , Pawel Cieslinski , Lukas Knips , Pawel Kurzynski , Wieslaw Laskowski

Quantum entanglement plays a pivotal role in various quantum information processing tasks. However, there still lacks a universal and effective way to detecting entanglement structures, especially for high-dimensional and multipartite…

Quantum Physics · Physics 2024-07-23 Rui Li , Junling Du , Zheng Qin , Shikun Zhang , Chunxiao Du , Yang Zhou , Zhisong Xiao

An entanglement witness is an observable with the property that a negative expectation value signals the presence of entanglement. The question arises how a witness can be improved if the expectation value of a second observable is known,…

Quantum Physics · Physics 2018-08-03 Mariami Gachechiladze , Nikolai Wyderka , Otfried Gühne

We present an experimentally feasible and efficient method for detecting entangled states with measurements that extend naturally to a tomographically complete set. Our detection criterion is based on measurements from subsets of a quantum…

Quantum Physics · Physics 2019-01-30 Joonwoo Bae , Beatrix C. Hiesmayr , Daniel McNulty

Machine learning is capable of discriminating phases of matter, and finding associated phase transitions, directly from large data sets of raw state configurations. In the context of condensed matter physics, most progress in the field of…

Statistical Mechanics · Physics 2017-12-06 Pedro Ponte , Roger G. Melko

We study the normal form of multipartite density matrices. It is shown that the correlation matrix (CM) separability criterion can be improved from the normal form we obtained under filtering transformations. Based on CM criterion the…

Quantum Physics · Physics 2015-05-13 Ming Li , Shao-Ming Fei , Zhi-Xi Wang

Entanglement plays a crucial role in quantum information science and many-body physics, yet quantifying it in mixed quantum many-body systems has remained a notoriously difficult problem. Here, we introduce families of quantitative…

Quantum Physics · Physics 2025-07-21 Poetri Sonya Tarabunga , Tobias Haug

Characterizing entanglement in quantum materials is crucial for advancing next-generation quantum technologies. Despite recent strides in witnessing entanglement in magnetic materials with distinguishable spin modes, quantifying…

Strongly Correlated Electrons · Physics 2025-03-27 Tongtong Liu , Luogen Xu , Jiarui Liu , Yao Wang

We study entanglement witnesses that can be constructed with regard to the geometrical structure of the Hilbert-Schmidt space, i.e. we present how to use these witnesses in the context of quantifying entanglement and the detection of bound…

Quantum Physics · Physics 2009-11-13 Reinhold A. Bertlmann , Philipp Krammer

The dimensionality of entanglement is a core tenet of quantum information processing, especially quantum communication and computation. While it is natural to think of this dimensionality in finite dimensional systems, many of the…

Quantum Physics · Physics 2025-09-04 Shuheng Liu , Jiajie Guo , Matteo Fadel , Qiongyi He , Marcus Huber , Giuseppe Vitagliano

An entanglement witness (EW) is an operator that allows to detect entangled states. We give necessary and sufficient conditions for such operators to be optimal, i.e. to detect entangled states in an optimal way. We show how to optimize…

Quantum Physics · Physics 2009-11-06 M. Lewenstein , B. Kraus , J. I. Cirac , P. Horodecki

Quantum networks form the backbone of long-distance quantum information processing. Genuine multipartite entanglement (GME) serves as a key indicator of network performance and overall state quality. However, the widely used methods for…

Quantum Physics · Physics 2026-01-13 Jing-Tao Qiu , D. M. Tong , Xiao-Dong Yu

One of the problems concerning entanglement witnesses (EWs) is the construction of them by a given set of operators. Here several multi-qubit EWs called stabilizer EWs are constructed by using the stabilizer operators of some given…

Quantum Physics · Physics 2009-11-13 M. A. Jafarizadeh , G. Najarbashi , Y. Akbari , H. Habibian

We extend the definition of entanglement witnesses based on structure factors to the case in which the position of the scatterers is quantized. This allows us to study entanglement detection in hybrid systems. We provide several examples…

Quantum Physics · Physics 2015-06-19 Massimo Borrelli , Matteo Rossi , Chiara Macchiavello , Sabrina Maniscalco

Violation of a Bell inequality certifies that the underlying state must be entangled in a device-independent way, although there may exist some entangled states which do not violate such an inequality. On the other hand, for every entangled…

Quantum Physics · Physics 2021-03-17 Chirag Srivastava , Shiladitya Mal , Aditi Sen De , Ujjwal Sen

Quantum entanglement is commonly assumed to be a central resource for quantum computing and quantum simulation. Nonetheless, the capability to detect it in many-body systems is severely limited by the absence of sufficiently scalable and…

Quantum Physics · Physics 2022-03-17 Irénée Frérot , Flavio Baccari , Antonio Acín

A conceptually simple and experimentally prevalent class of entanglement witnesses, known as fidelity witnesses, detect entanglement via a state's fidelity with a pure reference state. While existence proofs guarantee that a suitable…

Quantum Physics · Physics 2021-04-28 Gabriele Riccardi , Daniel E. Jones , Xiao-Dong Yu , Otfried Gühne , Brian T. Kirby

The support vector machine (SVM) is a well-established classification method whose name refers to the particular training examples, called support vectors, that determine the maximum margin separating hyperplane. The SVM classifier is known…

Statistics Theory · Mathematics 2022-06-15 Daniel Hsu , Vidya Muthukumar , Ji Xu

We consider multipartite quantum state discrimination and provide a specific relation between the properties of entanglement witness and quantum nonlocality inherent in the confidence of measurements. We first provide the definition of the…

Quantum Physics · Physics 2024-10-15 Donghoon Ha , Jeong San Kim

We discuss the problem of determining whether the state of several quantum mechanical subsystems is entangled. As in previous work on two subsystems we introduce a procedure for checking separability that is based on finding state…

Quantum Physics · Physics 2007-05-23 Andrew C. Doherty , Pablo A. Parrilo , Federico M. Spedalieri