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Related papers: Vectorization of quantum operations and its use

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Quantum tomography approaches typically consider a set of observables which we wish to measure, design a measurement scheme which measures each of the observables and then repeats the measurements as many times as necessary. We show that…

Quantum Physics · Physics 2025-01-28 Otto Veltheim , Esko Keski-Vakkuri

A general framework is presented which unifies the treatment of wavelet-like, quasidistribution, and tomographic transforms. Explicit formulas relating the three types of transforms are obtained. The case of transforms associated to the…

Mathematical Physics · Physics 2009-11-07 M. A. Man'ko , V. I. Man'ko , R. Vilela Mendes

We report complete characterization of an optical memory based on electromagnetically induced transparency. We recover the superoperator associated with the memory, under two different working conditions, by means of a quantum process…

Quantum Physics · Physics 2015-05-13 M. Lobino , C. Kupchak , E. Figueroa , A. I. Lvovsky

We present graphical representation for genaralized quantum measurements (POVM). We represent POVM elements as Bloch vectors and find the conditions these vectors should satisfy in order to describe realizable physical measurements. We show…

Quantum Physics · Physics 2007-05-23 Pawel Kurzynski , Andrzej Grudka

We discuss a new direction in the field of quantum information processing with neutral atoms. It is based on the use of microfabricated optical elements. With these elements versatile and integrated atom optical devices can be created in a…

Quantum Physics · Physics 2007-05-23 F. B. J. Buchkremer , R. Dumke , M. Volk , T. Muether , G. Birkl , W. Ertmer

We present the first complete optimization of quantum tomography, for states, POVMs, and various classes of transformations, for arbitrary prior ensemble and arbitrary representation, giving corresponding feasible experimental schemes.

Quantum Physics · Physics 2009-11-13 A. Bisio , G. Chiribella , G. M. D'Ariano , S. Facchini , P. Perinotti

Query Visualization (QV) is the problem of transforming a given query into a graphical representation that helps humans understand its meaning. This task is notably different from designing a Visual Query Language (VQL) that helps a user…

Databases · Computer Science 2022-08-03 Wolfgang Gatterbauer , Cody Dunne , H. V. Jagadish , Mirek Riedewald

There has been rapid development of systems that yield strong interactions between freely propagating photons in one dimension via controlled coupling to quantum emitters. This raises interesting possibilities such as quantum information…

We offer new results and new directions in the study of operator-valued kernels and their factorizations. Our approach provides both more explicit realizations and new results, as well as new applications. These include: (i) an explicit…

Quantum Physics · Physics 2025-03-04 Palle E. T. Jorgensen , James Tian

In this work, we propose novel families of positional encodings tailored to graph neural networks obtained with quantum computers. These encodings leverage the long-range correlations inherent in quantum systems that arise from mapping the…

Networks based on entangled quantum systems enable interesting applications in quantum information processing and the understanding of the resulting quantum correlations is essential for advancing the technology. We show that the theory of…

Quantum Physics · Physics 2021-05-12 Tristan Kraft , Cornelia Spee , Xiao-Dong Yu , Otfried Gühne

A factor-graph representation of quantum-mechanical probabilities (involving any number of measurements) is proposed. Unlike standard statistical models, the proposed representation uses auxiliary variables (state variables) that are not…

Information Theory · Computer Science 2017-06-13 Hans-Andrea Loeliger , Pascal O. Vontobel

We consider questions related to quantizing complex valued functions defined on a locally compact topological group. In the case of bounded functions, we generalize R. Werner's approach to prove the characterization of the associated normal…

Quantum Physics · Physics 2007-08-30 J. Kiukas , P. Lahti , K. Ylinen

For quantum computer circuits, it is proposed that they have, besides the presently used compact graphs, an expanded system of subgraphs, in line with the quantum mechanics superposition axiom. The representation of each process by these…

Quantum Physics · Physics 2013-10-02 Helio V. Fagundes

We present a quantum algorithm that additively approximates the value of a tensor network to a certain scale. When combined with existing results, this provides a complete problem for quantum computation. The result is a simple new way of…

Quantum Physics · Physics 2010-02-09 Itai Arad , Zeph Landau

This paper proposes a brain-inspired approach to quantum machine learning with the goal of circumventing many of the complications of other approaches. The fact that quantum processes are unitary presents both opportunities and challenges.…

Machine Learning · Computer Science 2019-05-16 Bruce MacLennan

By proceeding from a simple non-polarized formalism, we consider in detail the polarization procedure as applied to the generating equations of the quantum antibracket algebra, in terms of the parametrized generating operator.

High Energy Physics - Theory · Physics 2018-03-19 Igor A. Batalin , Peter M. Lavrov

Many classical encoding algorithms of Vector Quantization (VQ) of image compression that can obtain global optimal solution have computational complexity O(N). A pure quantum VQ encoding algorithm with probability of success near 100% has…

Multimedia · Computer Science 2009-11-11 Chao-Yang Pang , Zheng-Wei Zhou , Guang-Can Guo

In this paper, we present an overview of the recent developments of functional quantization of stochastic processes, with an emphasis on the quadratic case. Functional quantization is a way to approximate a process, viewed as a…

Probability · Mathematics 2013-04-03 Gilles Pagès

Quantum computation is based on implementing selected unitary transformations which represent algorithms. A generalized optimal control theory is used to find the driving field that generates a prespecified unitary transformation. The…

Quantum Physics · Physics 2009-11-07 Jose P. Palao , Ronnie Kosloff