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Related papers: Extremal Steering Assemblages

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We define an entanglement witness in a composite quantum system as an observable having nonnegative expectation value in every separable state. Then a state is entangled if and only if it has a negative expectation value of some…

Quantum Physics · Physics 2015-11-09 Leif Ove Hansen , Jan Myrheim

We analyse and experimentally demonstrate quantum steering using criteria based on generalised entropies and criteria with minimal assumptions based on the so-called dimension-bounded steering. Further, we investigate and compare their…

Quantum Physics · Physics 2020-07-14 Sabine Wollmann , Roope Uola , Ana C. S. Costa

Absolutely maximally entangled (AME) states are typically defined in homogeneous systems. However, the quantum system is more likely to be heterogeneous in a practical setup. In this work we pay attention to the construction of AME states…

Quantum Physics · Physics 2020-02-06 Yi Shen , Lin Chen

An extremal element of the convex set of composite quantum states in $M_2\otimes M_3$, whose marginals are all normalised identities has been constructed. It is found to be a mixed state and is entangled as well.

Quantum Physics · Physics 2013-04-22 S. Kanmani

We propose an experimentally feasible scheme to generate nonmaximal entanglement between two atomic ensembles. The degree of entanglement is readily tunable. The scheme involves laser manipulation of atomic ensembles, adjustable quarter-…

Quantum Physics · Physics 2007-05-23 Peng Xue , Guang-Can Guo

We describe how to device-independently generate a set of quantum states for which unambiguous state discrimination is not possible. First, we derive a formula that a certain non-signaling black box must satisfy. Then, we describe how to…

Quantum Physics · Physics 2015-06-03 Won-Young Hwang

Quantum entanglement does not necessarily imply Einstein-Podolsky-Rosen steering. We identify a \emph{boundary mechanism} that closes this gap when an entangled state meets the boundary of the trusted state space in a nondegenerate way. The…

Quantum Physics · Physics 2026-05-26 Yu-Xuan Zhang , Jing-Ling Chen

Recently, a framework was established to systematically construct novel universal resource states for measurement-based quantum computation using techniques involving finitely correlated states. With these methods, universal states were…

Quantum Physics · Physics 2009-08-04 J. -M. Cai , W. Dür , M. Van den Nest , A. Miyake , H. J. Briegel

In this letter we consider the problem of certification of quantum measurements with an arbitrary number of outcomes. We propose a simple scheme for certifying any set of $d$-outcome projective measurements which do not share any common…

Quantum Physics · Physics 2022-10-26 Shubhayan Sarkar , Debashis Saha , Remigiusz Augusiak

Protocols for testing or exploiting quantum correlations-such as entanglement, Bell nonlocality, and Einstein-Podolsky-Rosen steering- generally assume a common reference frame between two parties. Establishing such a frame is…

Quantum Physics · Physics 2018-09-12 Sabine Wollmann , Michael J. W. Hall , Raj B. Patel , Howard M. Wiseman , Geoff J. Pryde

Quantum steering is the phenomenon whereby one party (Alice) proves entanglement by "steering'' the system of another party (Bob) into distinct ensembles of states, by performing different measurements on her subsystem. Here, we investigate…

Quantum Physics · Physics 2024-04-04 Qiu-Cheng Song , Travis J. Baker , Howard M. Wiseman

So-called non-local boxes, which have been introduced as an idealization-in different respects-of the behavior of entangled quantum states, have been known to allow for unconditional bit commitment between the two involved parties. We show…

Quantum Physics · Physics 2010-12-14 Stefan Wolf , Juerg Wullschleger

Quantum statistics can be considered from the perspective of postquantum no-signaling theories in which either none or only a certain number of quantum systems are trusted. In these scenarios, the role of states is played by the so-called…

Entanglement, quantum steering and nonlocality are distinct quantum correlations which are the resources behind various of quantum information and quantum computation applications. However, a central question of determining the precise…

Quantum Physics · Physics 2018-12-05 Changbo Chen , Changliang Ren , Xiang-Jun Ye , Jing-Ling Chen

A bipartite state is said to be steerable if and only if it does not have a single system description, i.e., the bipartite state cannot be explained by a local hidden state model. Several steering inequalities have been derived using…

Quantum Physics · Physics 2017-02-01 Debasis Mondal , Tanumoy Pramanik , Arun Kumar Pati

One of the most important questions in quantum information theory is the so-called separability problem. It involves characterizing the set of separable (or, equivalently entangled) states among mixed states of a multipartite quantum…

Quantum Physics · Physics 2014-12-16 Michał Oszmaniec

In the paper we present results to develop an irreducible theory of complex systems in terms of self-organization processes of prime integer relations. Based on the integers and controlled by arithmetic only the self-organization processes…

Adaptation and Self-Organizing Systems · Physics 2007-05-23 Victor Korotkikh , Galina Korotkikh

We describe a particular class of pairs of quantum observables which are extremal in the convex set of all pairs of compatible quantum observables. The pairs in this class are constructed as uniformly noisy versions of two mutually unbiased…

Quantum Physics · Physics 2019-07-24 Claudio Carmeli , Gianni Cassinelli , Alessandro Toigo

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

Extremum seeking feedback is a powerful method to steer a dynamical system to an extremum of a partially or completely unknown map. It often requires advanced system-theoretic tools to understand the qualitative behavior of extremum seeking…

Dynamical Systems · Mathematics 2012-12-07 Hans-Bernd Dürr , Miloš S. Stanković , Christian Ebenbauer , Karl H. Johansson