English
Related papers

Related papers: A universal set of qubit quantum channels

200 papers

The method of complementary channel for analysis of reversibility (sufficiency) of a quantum channel with respect to families of input states (pure states for the most part) are considered and applied to Bosonic linear (quasi-free)…

Quantum Physics · Physics 2013-11-12 M. E. Shirokov

We consider a family of quantum channels characterized by the fact that certain (in general nonorthogonal) Pure states at the channel entrance are mapped to (tensor) Products of Pure states (PPP, hence "pcubed") at the complementary outputs…

Quantum Physics · Physics 2017-02-21 Vikesh Siddhu , Robert B. Griffiths

This article analyzes the algebraic structure of the set of all quantum channels and its subset consisting of quantum channels that have Holevo representation. The regularity of these semigroups under composition of mappings is analyzed. It…

Quantum Physics · Physics 2025-05-13 M. N. N. Namboodiri

Quantum channel, as the information transmitter, is an indispensable tool in quantum information theory. In this paper, we study a class of special quantum channels named the mixed-permutation channels. The properties of these channels are…

Quantum Physics · Physics 2024-01-15 Lin Zhang , Ming-Jing Zhao

We describe a broad dynamical-algebraic framework for analyzing the quantum control properties of a set of naturally available interactions. General conditions under which universal control is achieved over a set of subspaces/subsystems are…

Quantum Physics · Physics 2009-11-10 P. Zanardi , S. Lloyd

Quantum channels depending on a number of classical control parameters are considered. Assuming the stochastic fluctuations of the control parameters in the small errors limit it is shown that the channel fidelity is equal to the average…

Quantum Physics · Physics 2007-05-23 A. V. Kuzmin

We investigate the quantum channel consisting of two localized quantum systems that communicate through a scalar quantum field. We choose a scalar field rather than a tensor or vector field, such as the electromagnetic field, in order to…

Quantum Physics · Physics 2020-03-06 Petar Simidzija , Aida Ahmadzadegan , Achim Kempf , Eduardo Martin-Martinez

A quantum set is defined to be simply a set of nonzero finite-dimensional Hilbert spaces. Together with binary relations, essentially the quantum relations of Weaver, quantum sets form a dagger compact category. Functions between quantum…

Operator Algebras · Mathematics 2021-10-13 Andre Kornell

Implementing a qubit quantum computer in continuous-variable systems conventionally requires the engineering of specific interactions according to the encoding basis states. In this work, we present a unified formalism to conduct universal…

Quantum Physics · Physics 2016-09-06 Hoi-Kwan Lau , Martin B. Plenio

Understanding quantum channels and the strange behavior of their capacities is a key objective of quantum information theory. Here we study a remarkably simple, low-dimensional, single-parameter family of quantum channels with exotic…

Quantum Physics · Physics 2023-06-14 Felix Leditzky , Debbie Leung , Vikesh Siddhu , Graeme Smith , John A. Smolin

Given a unitary operator in a finite dimensional complex Hilbert space, its unitary reduction to a subspace is defined. The application to quantum graphs is discussed. It is shown how the reduction allows to generate the scattering matrices…

Quantum Physics · Physics 2025-01-10 L. L. Salcedo

Quantum correlation can be created by a local operation from some initially classical states. We prove that the necessary and sufficient condition for a local trace-preserving channel to create quantum correlation is that it is not a…

Quantum Physics · Physics 2012-03-08 Xueyuan Hu , Heng Fan , D. L. Zhou , Wu-Ming Liu

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

We give quantum circuits that simulate an arbitrary two-qubit unitary operator up to global phase. For several quantum gate libraries we prove that gate counts are optimal in worst and average cases. Our lower and upper bounds compare…

Quantum Physics · Physics 2013-05-29 Vivek V. Shende , Igor L. Markov , Stephen S. Bullock

This note introduces a family of circulant quantum channels -- a subclass of the mixed-permutation channels -- and investigates its key structural and operational properties. We show that the image of the circulant quantum channel is…

Quantum Physics · Physics 2026-02-04 Bing Xie , Lin Zhang

We present a both simple and comprehensive graphical calculus for quantum computing. In particular, we axiomatize the notion of an environment, which together with the earlier introduced axiomatic notion of classical structure enables us to…

Quantum Physics · Physics 2015-07-01 Bob Coecke , Simon Perdrix

We supply a rigorous proof that an open dense set of all possible 2-qubit gates G has the property that if the quantum circuit model is restricted to only permit swap of qubits lines and the application of G to pairs of lines, then the…

Group Theory · Mathematics 2014-05-21 Bela Bauer , Claire Levaillant , Michael Freedman

We construct a relativistic quantum communication channel between two localized qubit systems, mediated by a relativistic quantum field, that can achieve the theoretical maximum for the quantum capacity in arbitrary curved spacetimes using…

Quantum Physics · Physics 2025-07-03 Michael Kasprzak , Erickson Tjoa

A large-scalable quantum computer model, whose qubits are represented by the subspace subtended by the ground state and the single exciton state on semiconductor quantum dots, is proposed. A universal set of quantum gates in this system may…

Quantum Physics · Physics 2009-11-10 Kaiyu Yang , Shi-Liang Zhu , Z. D. Wang

We analyze a class of quantum operations based on a geometrical representation of $d-$level quantum system (or qudit for short). A sufficient and necessary condition of complete positivity, expressed in terms of the quantum Fourier…

Quantum Physics · Physics 2009-11-10 Runyao Duan , Zhengfeng Ji , Yuan Feng , Mingsheng Ying