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Related papers: Optimal representation of quantum channels

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We present a new method for quantum process tomography. The method enables us to efficiently estimate, with fixed precision, any of the parameters characterizing a quantum channel. It is selective since one can choose to estimate the value…

Quantum Physics · Physics 2008-01-08 Ariel Bendersky , Fernando Pastawski , Juan Pablo Paz

The JPEG algorithm compresses a digital image by filtering its high spatial-frequency components. Similarly, we introduce a quantum algorithm that uses the quantum Fourier transform to discard the high spatial-frequency qubits of an image,…

Quantum Physics · Physics 2024-01-09 Simone Roncallo , Lorenzo Maccone , Chiara Macchiavello

Quantum programs today are written at a low level of abstraction - quantum circuits akin to assembly languages - and the unitary parts of even advanced quantum programming languages essentially function as circuit description languages.…

Programming Languages · Computer Science 2025-12-02 Chris Heunen , Louis Lemonnier , Christopher McNally , Alex Rice

Quantum Network Tomography (QNT) offers a framework for end-to-end quantum channel characterization by strategically placing monitor nodes within the network. Building upon prior work on single-monitor placement, we study optimal monitor…

Identification over quantum broadcast channels is considered. As opposed to the information transmission task, the decoder only identifies whether a message of his choosing was sent or not. This relaxation allows for a double-exponential…

Quantum Physics · Physics 2023-08-02 Johannes Rosenberger , Christian Deppe , Uzi Pereg

Representations of quantum computations are almost always based on a tensor product $\otimes$-structure. This coincides with what we are able to execute in our experiments, as well as what we observe in Nature, but it makes certain familiar…

Quantum Physics · Physics 2021-11-05 Luca Mondada

Designing a mixed quantum channel is challenging due to the complexity of the transformations and the probabilistic mixtures of more straightforward channels involved. Fully characterizing a quantum channel generally requires preparing a…

Numerical Analysis · Mathematics 2025-06-30 Matthew M. Lin , Bing-Ze Lu

A quantum channel is a mapping which sends density matrices to density matrices. The estimation of quantum channels is of great importance to the field of quantum information. In this thesis two topics related to estimation of quantum…

Quantum Physics · Physics 2010-01-25 Caleb J. O'Loan

Quantum channels are known to provide qualitatively better information transfer capacities over their classical counterparts. Examples include quantum cryptography, quantum dense coding, and quantum teleportation. This is a short review on…

Quantum Physics · Physics 2015-03-19 Aditi Sen De , Ujjwal Sen

Most quantum compilers assume programs are reversible unitary circuits. This fits closed-system algorithms, but not open-system simulation, where the natural program objects are quantum channels describing non-unitary dynamics. We present a…

Quantum Physics · Physics 2026-05-25 Qifan Huang , Minbo Gao , Li Zhou , Mingsheng Ying

In the presented note we aim at exploring the possibility of abandoning complex numbers in the representation of quantum states and operations. We demonstrate a simplified version of quantum mechanics in which the states are represented…

Computational Physics · Physics 2017-12-21 J. A. Miszczak

Pauli channels are fundamental in the context of quantum computing as they model the simplest kind of noise in quantum devices. We propose a quantum algorithm for simulating Pauli channels and extend it to encompass Pauli dynamical maps…

Quantum Physics · Physics 2024-04-22 Tomas Basile , Carlos Pineda

This is an exposition of some of the aspects of quantum computation and quantum information that have connections with operator theory. After a brief introduction, we discuss quantum algorithms. We outline basic properties of quantum…

Operator Algebras · Mathematics 2007-05-23 David W. Kribs

We present a new framework for imaging and sensing based on utilizing a quantum computer to coherently process quantum information in an electromagnetic field. We describe the framework, its potential to provide improvements in imaging and…

Quantum Physics · Physics 2026-02-06 Mohan Sarovar

Quantum signal processing is a framework for implementing polynomial functions on quantum computers. To implement a given polynomial $P$, one must first construct a corresponding complementary polynomial $Q$. Existing approaches to this…

Quantum Physics · Physics 2025-06-16 Bjorn K. Berntson , Christoph Sünderhauf

Quantum machine learning techniques have been proposed as a way to potentially enhance performance in machine learning applications. In this paper, we introduce two new quantum methods for neural networks. The first one is a quantum…

Due to the rapid development of quantum computing, the compact representation of quantum operations based on decision diagrams has been received more and more attraction. Since variable orders have a significant impact on the size of the…

Quantum Physics · Physics 2022-07-26 Yonghong Li , Hao Miao

We present a quantum circuit representation consisting entirely of qubit initialisations (I), a network of controlled-NOT gates (C) and measurements with respect to different bases (M). The ICM representation is useful for optimisation of…

Quantum Physics · Physics 2015-09-15 Alexandru Paler , Ilia Polian , Kae Nemoto , Simon J. Devitt

In this work we aim at quantifying quantum channel output similarity. In order to achieve this, we introduce the notion of quantum channel superfidelity, which gives us an upper bound on the quantum channel fidelity. This quantity is…

Quantum Physics · Physics 2018-10-12 Łukasz Pawela , Zbigniew Puchała

Quantum computers are expected to be able to solve mathematical problems that cannot be solved using conventional computers. Many of these problems are of practical importance, especially in the areas of cryptography and secure…

Quantum Physics · Physics 2007-05-23 T. B. Pittman , B. C. Jacobs , J. D. Franson
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