English
Related papers

Related papers: Entanglement in mutually unbiased bases

200 papers

We present a study of the entanglement properties of Gaussian cluster states, proposed as a universal resource for continuous-variable quantum computing. A central aim is to compare mathematically-idealized cluster states defined using…

Quantum Physics · Physics 2010-11-30 Hugo Cable , Daniel E. Browne

We show that entanglement of pure multi-party states can be quantified by means of quantum uncertainties of certain basic observables through the use of measure that has been initially proposed in [10] for bipartite systems.

Quantum Physics · Physics 2016-08-16 Alexander A. Klyachko , Barış Öztop , Alexander S. Shumovsky

We analyze some special properties of a system of two qubits, and in particular of the so-called Bell basis for this system, which have played an important role in recent papers on entanglement of qubits. In particular, we show which of…

Quantum Physics · Physics 2009-10-31 K. G. H. Vollbrecht , R. F. Werner

Distinguishing physical processes is one of the fundamental problems in quantum physics. Although distinguishability of quantum preparations and quantum channels have been studied considerably, distinguishability of quantum measurements…

Quantum Physics · Physics 2021-04-13 Chandan Datta , Tanmoy Biswas , Debashis Saha , Remigiusz Augusiak

From the consideration of measuring bipartite mixed states by separable pure states, we introduce algebraic sets in complex projective spaces for bipartite mixed states as the degenerating locus of the measurement. These algebraic sets are…

Quantum Physics · Physics 2007-05-23 Hao Chen

The entanglement detection via local measurements can be experimentally implemented. Based on mutually unbiased measurements and general symmetric informationally complete positive-operator-valued measures, we present separability criteria…

Quantum Physics · Physics 2018-03-30 Shu-Qian Shen , Ming Li , Xianqing Li-Jost , Shao-Ming Fei

We propose a new approach to the problem of defining the degree of entanglement between two particles in a pure state with Hilbert spaces of arbitrary finite dimensions. The central idea is that entanglement gives rise to correlations…

Quantum Physics · Physics 2007-05-23 Markus A. Cirone

We present a new approach to the analysis of entanglement in smooth bipartite continuous-variable states. One or both parties perform projective filterings via preliminary measurements to determine whether the system is located in some…

Quantum Physics · Physics 2009-11-13 H. -C. Lin , A. J. Fisher

The paper contains a brief review of an approach to quantum entanglement based on analysis of dynamic symmetry of systems and quantum uncertainties, accompanying the measurement of mean value of certain basic observables. The latter are…

Quantum Physics · Physics 2009-11-11 Alexander A. Klyachko , Alexander S Shumovsky

Entanglement is a fundamental feature of quantum mechanics and holds great promise for enhancing metrology and communications. Much of the focus of quantum metrology so far has been on generating highly entangled quantum states that offer…

Entanglement are the non-local correlations permitted by quantum theory, believed to play a fundamental role in a quantum computer. We have investigated these correlations in a number of theoretical models for condensed matter systems. Such…

Quantum Physics · Physics 2007-05-23 Stein Olav Skrøvseth

Squashed entanglement and its universal upper bound, the quantum conditional mutual information, are faithful measures of bipartite quantum correlations defined in terms of multipartitions. As such, they are sensitive to the fine-grain…

Quantum Physics · Physics 2023-04-12 Alfonso Maiellaro , Francesco Romeo , Roberta Citro , Fabrizio Illuminati

We present a general description of separable states in Quantum Mechanics. In particular, our result gives an easy proof that inseparabitity (or entanglement) is a pure quantum (noncommutative) notion. This implies that distinction between…

Quantum Physics · Physics 2007-05-23 Adam W. Majewski

Measurements with randomly chosen settings determine many important properties of quantum states without the need for a shared reference frame or calibration. They naturally emerge in the context of quantum communication and quantum…

Finding all the mutually unbiased bases in various dimensions is a problem of fundamental interest in quantum information theory and pure mathematics. The general problem formulated in finite-dimensional Hilbert spaces is open. In the…

Quantum Physics · Physics 2009-09-25 Julia Evans , Ross Duncan , Alex Lang , Prakash Panangaden

Suppose an experimentalist wishes to verify that his apparatus produces entangled quantum states. A finite amount of data cannot conclusively demonstrate entanglement, so drawing conclusions from real-world data requires statistical…

Quantum Physics · Physics 2010-10-22 Robin Blume-Kohout , Jun O. S. Yin , S. J. van Enk

Entanglement is the central resource of quantum information processing and the precise characterization of entangled states is a crucial issue for the development of quantum technologies. This leads to the necessity of a precise,…

We propose a directly measurable criterion for the entanglement of two qubits. We compare the criterion with other criteria, and we find that for pure states, and some mixed states, it coincides with the state's concurrency. The measure can…

Quantum Physics · Physics 2016-08-16 Hoshang Heydari , Gunnar Björk , Luis Sánchez-Soto

We construct general schemes for multi-partite quantum secret sharing using multi-level systems, and find that the consistent conditions for valid measurements can be summarized in two simple algebraic conditions. The scheme using the very…

Quantum Physics · Physics 2015-07-22 I-Ching Yu , Feng-Li Lin , Ching-Yu Huang

Mutually unbiased bases encapsulate the concept of complementarity - the impossibility of simultaneous knowledge of certain observables - in the formalism of quantum theory. Although this concept is at the heart of quantum mechanics, the…

Quantum Physics · Physics 2009-01-19 Tomasz Paterek , Borivoje Dakic , Caslav Brukner