English
Related papers

Related papers: Parametrization of Quantum States and Channels

200 papers

A preferred form for the path integral discretization is suggested that allows the implementation of canonical transformations in quantum theory.

High Energy Physics - Theory · Physics 2009-10-28 A. Y. Shiekh

In quantum information processing it may be possible to have efficient computation and secure communication beyond the limitations of classical systems. In a fundamental point of view, however, evolution of quantum systems by the laws of…

Quantum Physics · Physics 2017-09-21 Joonwoo Bae

Based on the {\it nonlinear coherent states} method, a general and simple algebraic formalism for the construction of \textit{`$f$-deformed intelligent states'} has been introduced. The structure has the potentiality to apply to systems…

Quantum Physics · Physics 2009-08-04 M. K. Tavassoly , A. Parsaiean

The notion of quantum matrix pairs is defined. These are pairs of matrices with non-commuting entries, which have the same pattern of internal relations, q-commute with each other under matrix multiplication, and are such that products of…

Quantum Algebra · Mathematics 2007-05-23 J. E. Nelson , R. F. Picken

We review some applications of entanglement to improve quantum measurements and communication, with the main focus on the optical implementation of quantum information processing. The evolution of continuos variable entangled states in…

Quantum Physics · Physics 2007-05-23 M. G. A. Paris , G. M. D'Ariano , P. Lo Presti , P. Perinotti

Convenient parameterizations of matrices in terms of vectors transform (certain classes of) matrix equations into covariant (hence rotation-invariant) vector equations. Certain recently introduced such parameterizations are tersely…

Exactly Solvable and Integrable Systems · Physics 2009-11-10 M. Bruschi , F. Calogero

Quantum Process Tomography (QPT) is a powerful tool to characterize quantum operations, but it requires considerable resources making it impractical for more than 2-qubit systems. This work proposes an alternative approach that requires…

Quantum Physics · Physics 2022-05-18 Vicente Leyton-Ortega , Tyler Kharazi , Raphael C. Pooser

We investigate the separability of quantum states based on covariance matrices. Separability criteria are presented for multipartite states. The lower bound of concurrence proposed in Phys. Rev. A. 75, 052320 (2007) is improved by…

Quantum Physics · Physics 2009-09-29 Ming Li , Shao-Ming Fei , Zhi-Xi Wang

Quantum information theory is the study of the achievable limits of information processing within quantum mechanics. Many different types of information can be accommodated within quantum mechanics, including classical information, coherent…

Quantum Physics · Physics 2007-05-23 M. A. Nielsen

Symmetric quantum states are fascinating objects. They correspond to multipartite systems that remain invariant under particle permutations. This symmetry is reflected in their compact mathematical characterisation but also in their unique…

Quantum Physics · Physics 2025-07-15 Carlo Marconi , Guillem Müller-Rigat , Jordi Romero-Pallejà , Jordi Tura , Anna Sanpera

The relation between completely positive maps and compound states is investigated in terms of the notion of quantum conditional probability.

Quantum Physics · Physics 2007-05-23 M. Asorey , A. Kossakowski , G. Marmo , E. C. G. Sudarshan

Characterizing complex quantum systems is a vital task in quantum information science. Quantum tomography, the standard tool used for this purpose, uses a well-designed measurement record to reconstruct quantum states and processes. It is,…

Quantum Physics · Physics 2015-12-10 Amir Kalev , Robert L. Kosut , Ivan H. Deutsch

We address the problem of completely characterizing multi-particle states including loss of information to unobserved degrees of freedom. In systems where non-classical interference plays a role, such as linear-optics quantum gates, such…

Quantum Physics · Physics 2009-11-13 R. B. A. Adamson , L. K. Shalm , M. W. Mitchell , A. M. Steinberg

We address the problem of information completeness of quantum measuremets in connection to quantum state tomography and with particular concern to quantum symplectic tomography. We put forward some non-trivial situations where…

Quantum Physics · Physics 2009-11-13 Grigori G. Amosov , Stefano Mancini , Vladimir I. Man'ko

Quantum state preparation involves preparing a target state from an initial system, a process integral to applications such as quantum machine learning and solving systems of linear equations. Recently, there has been a growing interest in…

Quantum Physics · Physics 2024-05-08 Shuwen Kan , Miguel Palma , Zefan Du , Samuel A Stein , Chenxu Liu , Juntao Chen , Ang Li , Ying Mao

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

The communication of directions using quantum states is a useful laboratory test for some basic facts of quantum information. For a system of spin-1/2 particles there are different quantum states that can encode directions. This information…

Quantum Physics · Physics 2007-05-23 E. Bagan , M. Baig , R. Munoz-Tapia

Entropic quantifiers of states lie at the cornerstone of the quantum information theory. While a quantum state can be abstracted as a device that only has outputs, the most general quantum device is a quantum channel that also has inputs.…

Quantum Physics · Physics 2019-03-27 Xiao Yuan

The aim of the present paper is twofold. First, to give the main ideas behind quantum computingand quantum information, a field based on quantum-mechanical phenomena. Therefore, a shortreview is devoted to (i) quantum bits or qubits (and…

Quantum Physics · Physics 2018-11-22 Maurice Robert Kibler

Quantum channels represent a broad spectrum of operations crucial to quantum information theory, encompassing everything from the transmission of quantum information to the manipulation of various resources. In the domain of states, the…

Quantum Physics · Physics 2025-05-15 Gilad Gour , Doyeong Kim , Takla Nateeboon , Guy Shemesh , Goni Yoeli