English
Related papers

Related papers: Universal nonlinear entanglement witnesses

200 papers

We formulate some properties of a set of several mutually unbiased measurements. These properties are used for deriving entropic uncertainty relations. Applications of mutually unbiased measurements in entanglement detection are also…

Quantum Physics · Physics 2015-05-07 Alexey E. Rastegin

We discuss particle entanglement in systems of indistinguishable bosons and fermions, in finite Hilbert spaces, with focus on operational measures of quantum correlations. We show how to use von Neumann entropy, Negativity and entanglement…

Quantum Physics · Physics 2013-02-22 Fernando Iemini , Reinaldo O. Vianna

Protocols have been previously proposed to certify the presence of an entangled measurement in a fully device-independent manner. Here, I provide models for these protocols in which the claimed measurement is not entangled, and demonstrate…

Quantum Physics · Physics 2026-02-18 Peter Bierhorst

A general scheme to seek for the relations between entanglement and bservables is proposed in principle. In two-qubit systems with enough general Hamiltonian, we find the entanglement to be the functions of observables for six kinds of…

Quantum Physics · Physics 2007-05-23 An Min Wang

Having common reference frames or aligned coordinate systems, is one of the presumptions in witnessing entanglement in a two-party state possessed by two remote parties. This assumption may fail for many reasons. With an unlimited supply of…

Quantum Physics · Physics 2024-05-31 Vahid Jannessary , Fatemeh Rezazadeh , Sadegh Raeisi , Vahid Karimipour

We introduce a general scheme to detect various multiparticle entanglement structures from global non-permutationally invariant observables. In particular, we derive bounds on the variance of non-permutationally invariant and collective…

Quantum Physics · Physics 2017-08-24 Oliver Marty , Marcus Cramer , Giuseppe Vitagliano , Geza Toth , Martin B. Plenio

Absolutely separable states form a special subset of the set of all separable states, as they remain separable under any global unitary transformation unlike other separable states. In this work we consider the set of absolutely separable…

Quantum Physics · Physics 2015-06-18 Nirman Ganguly , Jyotishman Chatterjee , A. S. Majumdar

It is well-known that the violation of a local uncertainty relation can be used as an indicator for the presence of entanglement. Unfortunately, the practical use of these non-linear witnesses has been limited to few special cases in the…

The entanglement produced by a bilinear Hamiltonian in continuous variables has been thoroughly studied and widely used. In contrast, the physics of entanglement resulting from nonlinear interaction described by partially degenerate…

Quantum Physics · Physics 2021-11-10 Da Zhang , David Barral , Yin Cai , Yanpeng Zhang , Min Xiao , Kamel Bencheikh

We introduce detector-level entanglement, a unified entanglement concept for identical particles that takes into account the possible deletion of many-particle which-way information through the detection process. The concept implies a…

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

The problem of entanglement detection for arbitrary spin systems is analyzed. We demonstrate how a single measurement of the squared total spin can probabilistically discern separable from entangled many-particle states. For achieving this…

Quantum Physics · Physics 2016-07-29 Eliahu Cohen , Tobias Hansen , Nissan Itzhaki

It was recently realised that quantum theory allows for so-called causally nonseparable processes, which are incompatible with any definite causal order. This was first suggested on a rather abstract level by the formalism of process…

Quantum Physics · Physics 2016-05-20 Cyril Branciard

In their 2002 article, Ghirardi, Marinatto and Weber have proposed a formal analysis of the entanglement properties for a system consisting of N distinguishable particles. Their analysis leads to the differentiation of three possible…

Quantum Physics · Physics 2011-05-10 Tomasz Bigaj

The experimental detection of quantum entanglement is of great importance in quantum information processing. We present two separability criteria based on the generalized realignment moments. By incorporating additional parameters, these…

Quantum Physics · Physics 2026-02-25 Xiaofen Huang , Xishun Zhu , Bin Chen , Naihuan Jing , Shao-Ming Fei

Multipartite entanglement detection is crucial for the develop of quantum information science and quantum computation, communication, simulation and metrology tasks. In contrast to experiments, where several handreds of qubits have been…

Quantum Physics · Physics 2024-11-06 Xiao-yu Chen

Observability is a modelling property that describes the possibility of inferring the internal state of a system from observations of its output. A related property, structural identifiability, refers to the theoretical possibility of…

Quantitative Methods · Quantitative Biology 2018-12-12 Alejandro F. Villaverde

We consider multipartite quantum state discrimination and show that the minimum-error discrimination by separable measurements is closely related to the concept of entanglement witness. Based on the properties of entanglement witness, we…

Quantum Physics · Physics 2023-04-25 Donghoon Ha , Jeong San Kim

We examine various notions related with the optimality for entanglement witnesses arising from Choi type positive linear maps. We found examples of optimal entanglement witnesses which are non-decomposable, but which are not…

Quantum Physics · Physics 2012-09-10 Kil-Chan Ha , Seung-Hyeok Kye

Multipartite entanglement is one of the crucial resources in quantum information processing tasks such as quantum metrology, quantum computing and quantum communications. It is essential to verify not only the multipartite entanglement, but…

Quantum Physics · Physics 2024-06-12 Kai Wu , Zhihua Chen , Zhen-Peng Xu , Zhihao Ma , Shao-Ming Fei