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Related papers: Entanglement detection via mutually unbiased bases

200 papers

We present an approach to characterize genuine multiparticle entanglement using appropriate approximations in the space of quantum states. This leads to a criterion for entanglement which can easily be calculated using semidefinite…

Quantum Physics · Physics 2011-05-13 Bastian Jungnitsch , Tobias Moroder , Otfried Gühne

A new family of positive, trace-preserving maps is introduced. It is defined using the mutually unbiased measurements, which generalize the notion of mutual unbiasedness of orthonormal bases. This family allows one to define entanglement…

Quantum Physics · Physics 2021-11-30 Katarzyna Siudzińska , Dariusz Chruściński

Quantum measurements based on mutually unbiased bases (MUB) play crucial roles in foundational studies and quantum information processing. It is known that there exist inequivalent MUB, but little is known about their operational…

Quantum Physics · Physics 2023-11-14 Wen-Zhe Yan , Yunting Li , Zhibo Hou , Huangjun Zhu , Guo-Yong Xiang , Chuan-Feng Li , Guang-Can Guo

Quantum measurements based on mutually unbiased bases are commonly used in quantum information processing, as they are generally viewed as being maximally incompatible and complementary. Here we quantify precisely the degree of…

Quantum Physics · Physics 2020-04-20 Sébastien Designolle , Paul Skrzypczyk , Florian Fröwis , Nicolas Brunner

A sufficient condition for entanglement in two-mode continuous systems is constructed based on interference visibility and the uncertainty of the total particle number. The observables to be measured (particle numbers and particle number…

Quantum Physics · Physics 2007-05-23 Geza Toth , Christoph Simon , Juan Ignacio Cirac

This is a review of the problem of Mutually Unbiased Bases in finite dimensional Hilbert spaces, real and complex. Also a geometric measure of "mubness" is introduced, and applied to some recent calculations in six dimensions (partly done…

Quantum Physics · Physics 2015-06-26 Ingemar Bengtsson

In its vast majority entanglement verification is examined either in the complete characterized or totally device independent scenario. The assumptions imposed by these extreme cases are often either too weak or strong for real experiments.…

Quantum Physics · Physics 2013-05-30 Tobias Moroder , Oleg Gittsovich

The uncertainty principle, which bounds the uncertainties involved in obtaining precise outcomes for two complementary variables defining a quantum particle, is a crucial aspect in quantum mechanics. Recently, the uncertainty principle in…

Quantum Physics · Physics 2012-04-24 Chuan-Feng Li , Jin-Shi Xu , Xiao-Ye Xu , Ke Li , Guang-Can Guo

Entanglement, which is an essential characteristic of quantum mechanics, is the key element in potential practical quantum information and quantum communication systems. However, there are many open and fundamental questions (relating to…

Quantum Physics · Physics 2015-05-18 G. W. Ford , Yang Gao , R. F. O'Connell

Witnessing entanglement is crucial in quantum information processing. With properly preparing ancillary states, it has been shown previously that genuine entanglement can be witnessed without trusting measurement devices. In this work, we…

Quantum Physics · Physics 2016-07-28 Qi Zhao , Xiao Yuan , Xiongfeng Ma

A set of mutually unbiased bases (MUBs) is said to be unextendible if there does not exist another basis that is unbiased with respect to the given set. Here, we prove the existence of smaller sets of MUBs in prime-squared dimensions…

Quantum Physics · Physics 2015-08-25 Vishakh Hegde , Prabha Mandayam

We explore the possibility of entanglement detection in continuous variable systems by entanglement witnesses based on covariance matrices, constructible from random homodyne measurements. We propose new linear constraints characterizing…

Quantum Physics · Physics 2021-01-20 Tatiana Mihaescu , Hermann Kampermann , Giulio Gianfelici , Aurelian Isar , Dagmar Bruss

We derive a general framework to identify genuinely multipartite entangled mixed quantum states in arbitrary-dimensional systems and show in exemplary cases that the constructed criteria are stronger than those previously known. Our…

Quantum Physics · Physics 2013-05-29 Marcus Huber , Florian Mintert , Andreas Gabriel , Beatrix C. Hiesmayr

Entanglement witnesses are invaluable for efficient quantum entanglement certification without the need for expensive quantum state tomography. Yet, standard entanglement witnessing requires multiple measurements and its bounds can be…

Quantum Physics · Physics 2017-03-22 Farid Shahandeh , Martin Ringbauer , Juan C. Loredo , Timothy C. Ralph

Based on maximally entangled states, we explore the constructions of mutually unbiased bases in bipartite quantum systems. We present a new way to construct mutually unbiased bases by difference matrices in the theory of combinatorial…

Quantum Physics · Physics 2022-10-05 Yajuan Zang , Zihong Tian , Hui-Juan Zuo , Shao-Ming Fei

How can one prove that a given state is entangled? In this paper we review different methods that have been proposed for entanglement detection. We first explain the basic elements of entanglement theory for two or more particles and then…

Quantum Physics · Physics 2009-04-16 Otfried Gühne , Geza Toth

We propose experimentally feasible separability criteria for bipartite systems based on local symmetric measurements. Through detailed examples, we demonstrate that our criteria can detect entanglement more effectively compared to existing…

Quantum Physics · Physics 2025-12-12 Yu Lu , Wen Zhou , Meng Su , Hong-Xing Wu , Shao-Ming Fei , Zhi-Xi Wang

We construct a single observable measurement of which mean value on four copies of an {\it unknown} two-qubit state is sufficient for unambiguous decision whether the state is separable or entangled. In other words, there exists a universal…

Quantum Physics · Physics 2015-06-26 Remigiusz Augusiak , Maciej Demianowicz , Pawel Horodecki

An efficient method for assessing the quality of quantum state tomography is developed. Special attention is paid to the tomography of multipartite systems in terms of unbiased measurements. Although the overall reconstruction errors of…

Quantum Physics · Physics 2013-11-19 J. Rehacek , Z. Hradil , A. B. Klimov , G. Leuchs , L. L. Sanchez-Soto

We search a simplest and minimal way to determine whether a given quantum system is entangled or separable. For this end, we propose binary correlation measurements in which restricted knowledge of only zero or non-zero correlations is…

Quantum Physics · Physics 2021-06-29 Toru Ohira