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Related papers: Unambiguous discrimination of mixed states: A desc…

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Entanglement characteristics of a pair coherent state is studied using entanglement of superposition. It is demonstrated only few states in the expansion of a pair coherent state, in a harmonic oscillator basis, contribute significantly to…

Quantum Physics · Physics 2007-08-06 Jitesh R. Bhatt , Prasanta K. Panigrahi

In this paper, we shall show that the question of quanum state unambiguous discrimination can be solved by reducing it to the known problem of quantum states filtering.

Quantum Physics · Physics 2015-09-01 Xiaohua Wu , Yu Shaolan , Zhou Tao

Here we develop two quantum-computational models for supervised and unsupervised classification tasks in quantum world. Presuming that the states of a set of given quantum systems (or objects) belong to one of two known classes, the…

Quantum Physics · Physics 2021-04-02 Farzad Shahi , Ali T. Rezakhani

Recently, a new and powerful separability criterion was introduced in [O. Rudolph, quant-ph/0202121] and [Chen {\it et al.}, quant-ph/0205017]. Composing the main idea behind the above criterion and the necessary and sufficient condition in…

Quantum Physics · Physics 2007-05-23 Michal Horodecki , Pawel Horodecki , Ryszard Horodecki

We provide necessary and sufficient conditions for separability of mixed states. As a result we obtain a simple criterion of separability for $2\times2$ and $2\times3$ systems. Here, the positivity of the partial transposition of a state is…

Quantum Physics · Physics 2009-10-30 Michal Horodecki , Pawel Horodecki , Ryszard Horodecki

We introduce algebraic sets in the complex projective spaces for the mixed states in bipartite quantum systems as their invariants under local unitary operations. The algebraic sets of the mixed state have to be the union of the linear…

Quantum Physics · Physics 2007-05-23 Hao Chen

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

Quantum mechanics forbids deterministic discrimination among non-orthogonal states. Nonetheless, the capability to distinguish nonorthogonal states unambiguously is an important primitive in quantum information processing. In this work, we…

Quantum Physics · Physics 2016-08-16 Masoud Mohseni , Aephraim M. Steinberg , János A. Bergou

We present a solution of the problem of the optimal unambiguous comparison of two ensembles of unknown quantum states (psi_1)^k and (psi_2)^l. We consider two cases: 1) The two unknown states psi_1 and psi_2 are arbitrary states of qudits.…

Quantum Physics · Physics 2008-12-11 Michal Sedlak , Mario Ziman , Vladimir Buzek , Mark Hillery

Separability problem, to decide whether a given state is entangled or not, is a fundamental problem in quantum information theory. We propose a powerful and computationally simple separability criterion, which allows us to detect the…

Quantum Physics · Physics 2009-11-13 Cheng-Jie Zhang , Yong-Sheng Zhang , Shun Zhang , Guang-Can Guo

We consider an unambiguous identification of an unknown coherent state with one of two unknown coherent reference states. Specifically, we consider two modes of an electromagnetic field prepared in unknown coherent states alpha_1 and…

Quantum Physics · Physics 2008-12-11 Michal Sedlak , Mario Ziman , Ondrej Pribyla , Vladimir Buzek , Mark Hillery

Complete solutions are given in a closed analytic form for unambiguous discrimination of three general pure states with real mutual inner products. For this purpose, we first establish some general results on unambiguous discrimination of n…

Quantum Physics · Physics 2010-10-05 H. Sugimoto , T. Hashimoto , M. Horibe , A. Hayashi

Quantum state elimination measurements tell us what states a quantum system does not have. This is different from state discrimination, where one tries to determine what the state of a quantum system is, rather than what it is not. Apart…

We show that the quantum measurement known as the pretty good measurement can be used to identify an unknown quantum state picked from any set of $n$ mixed states that have pairwise fidelities upper-bounded by a constant below 1, given…

Quantum Physics · Physics 2019-11-11 Ashley Montanaro

This paper aims at comparing two coupling approaches as basic layers for building clustering criteria, suited for modularizing and clustering very large networks. We briefly use "optimal transport theory" as a starting point, and a way as…

Discrete Mathematics · Computer Science 2021-03-19 Pierre Bertrand , Michel Broniatowski , Jean-François Marcotorchino

We introduce a generalization of the set of completely positive matrices that we call "pairwise completely positive" (PCP) matrices. These are pairs of matrices that share a joint decomposition so that one of them is necessarily positive…

Quantum Physics · Physics 2019-05-30 Nathaniel Johnston , Olivia MacLean

We extend the classification of mixed states of quantum systems composed of arbitrary number of subsystems of arbitrary dimensions. This extended classification is complete in the sense of partial separability and gives 1+18+1 partial…

Quantum Physics · Physics 2012-10-03 Szilárd Szalay , Zoltán Kökényesi

For the formal verification and design of control systems, abstractions with quantified accuracy are crucial. This is especially the case when considering accurate deviation bounds between a stochastic continuous-state model and its finite…

Systems and Control · Electrical Eng. & Systems 2022-01-19 B. C. van Huijgevoort , S. Haesaert

With any state of a multipartite quantum system its separability polytope is associated. This is an algebro-topological object (non-trivial only for mixed states) which captures the localisation of entanglement of the state. Particular…

Quantum Physics · Physics 2015-06-26 Roman R. Zapatrin

Unambiguously distinguishing between nonorthogonal but linearly independent quantum states is a challenging problem in quantum information processing. In this work, an exact analytic solution to an optimum measurement problem involving an…

Quantum Physics · Physics 2009-11-13 M. A. Jafarizadeh , M. Rezaei , N. Karimi , A. R. Amiri