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Related papers: A new approach to characterize qubit channels

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Gaussian quantum channels are relevant operations in continuous variable systems. In general, given an arbitrary state, the action on it is well-known provided that the quantum channels are completely characterized. In this work, we…

Quantum Physics · Physics 2025-05-20 Jonas F. G. Santos , Carlos H. S. Vieira , Wilder R. Cardoso

We characterise Gaussian quantum channels that are Gaussian incompatibility breaking, that is, transform every set of Gaussian measurements into a set obtainable from a joint Gaussian observable via Gaussian postprocessing. Such channels…

Quantum Physics · Physics 2015-09-02 Teiko Heinosaari , Jukka Kiukas , Jussi Schultz

Time-varying quantum channels are essential for modeling realistic quantum systems with evolving noise properties. Here, we consider Gaussian lossy channels varying from one use to another and we employ neural networks to classify, regress,…

We give necessary and sufficient conditions for a Gaussian quantum channel to have a dilation involving a passive, i.e., number-preserving unitary. We then establish a normal form of such channels: any passively dilatable channel is the…

Quantum Physics · Physics 2017-04-27 Martin Idel , Robert Koenig

A complete degradability analysis of one-mode Gaussian Bosonic channels is presented. We show that apart from the class of channels which are unitarily equivalent to the channels with additive classical noise, these maps can be…

Quantum Physics · Physics 2009-11-13 F. Caruso , V. Giovannetti , A. S. Holevo

The Glauber-Sudarshan diagonal `weight' function provides a natural divide between the quantum-optical notion of classical and nonclassical states of continuous variables systems. Based on this demarcation, a channel is said to be…

Quantum Physics · Physics 2016-04-28 Krishna Kumar Sabapathy

We put forward a measure based on Gaussian steering to quantify the non-Markovianity of continuous-variable (CV) Gaussian quantum channels. We employ the proposed measure to assess and compare the non-Markovianity of a quantum Brownian…

Quantum Physics · Physics 2021-11-17 Massimo Frigerio , Samaneh Hesabi , Davood Afshar , Matteo G. A. Paris

The action of qubit channels on projective measurements on a qubit state is used to establish an equivalence between channels and properties of generalized measurements characterized by bias and sharpness parameters. This can be interpreted…

Quantum Physics · Physics 2021-11-03 Javid Naikoo , Subhashish Banerjee , A. K. Pan , Sibasish Ghosh

A classification of one-mode Gaussian channels is given up to canonical unitary equivalence. A complementary to the quantum channel with additive classical Gaussian noise is described providing an example of one-mode Gaussian channel which…

Quantum Physics · Physics 2010-12-30 A. S. Holevo

The set of quantum Gaussian channels acting on one bosonic mode can be classified according to the action of the group of Gaussian unitaries. We look for bounds on the classical capacity for channels belonging to such a classification.…

Quantum Physics · Physics 2011-03-03 Cosmo Lupo , Stefano Pirandola , Paolo Aniello , Stefano Mancini

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 full experimental characterization of continuous variable quantum communication channels established by shared entanglement together with local operations and classical communication. The resulting teleportation channel was…

Quantum Physics · Physics 2009-11-13 James DiGuglielmo , Boris Hage , Alexander Franzen , Jaromir Fiurasek , Roman Schnabel

This work presents a differentiable geometric parameterization of quantum channels in Kraus representation, which can be efficiently probed to find an unknown quantum channel. We explore its feasibility in finding the quasi inverse…

Quantum Physics · Physics 2025-12-02 Zain Ateeq , Muhammad Faryad

A noisy Gaussian channel is defined as a channel in which an input field mode is subjected to random Gaussian displacements in phase space. We introduce the quantum fidelity of a Gaussian channel for pure and mixed input states, and we…

Quantum Physics · Physics 2007-05-23 Carlton M. Caves , Krzysztof Wodkiewicz

In this paper we are interested to model quantum signal by statistical signal processing methods. The Gaussian distribution has been considered for the input quantum signal as Gaussian state have been proven to a type of important robust…

Quantum Physics · Physics 2023-02-17 Mouli Chakraborty , Harun Siljak , Indrakshi Dey , Nicola Marchetti

The Gaussian state description of continuous variables is adapted to describe the quantum interaction between macroscopic atomic samples and continuous-wave light beams. The formalism is very efficient: a non-linear differential equation…

Quantum Physics · Physics 2007-05-23 L. B. Madsen , K. Mølmer

We introduce a novel strategy, based on the use of modular variables, to encode and deterministically process quantum information using states described by continuous variables. Our formalism leads to a general recipe to adapt existing…

Quantum Physics · Physics 2014-06-26 A. Ketterer , S. P. Walborn , A. Keller , T. Coudreau , P. Milman

Teleportation of optical field states (as continuous quantum variables) is usually described in terms of Wigner functions. This is in marked contrast to the theoretical treatment of teleportation of qubits. In this paper we show that by…

Mathematical Physics · Physics 2009-06-11 S. Nagamachi , E. Brüning

This article provides an elementary introduction to Gaussian channels and their capacities. We review results on the classical, quantum, and entanglement assisted capacities and discuss related entropic quantities as well as additivity…

Quantum Physics · Physics 2009-05-15 J. Eisert , M. M. Wolf

We investigate the action of the depolarising (qubit) channel on permutation invariant input states. More specifically, we raise the question on which invariant subspaces the output of the depolarising channel, given such special input, is…

Quantum Physics · Physics 2013-02-27 Janis Noetzel