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Related papers: Quantumness of channels

200 papers

We investigate the coherence of quantum channels and establish a resource theory for quantifying the coherence of quantum channels via Choi matrix. To this aim, we define the incoherent channels and incoherent superchannels. This theory…

Quantum Physics · Physics 2019-11-12 Jianwei Xu

Local noise can produce quantum correlations on an initially classically correlated state, provided that it is not represented by a unital or semi-classical channel \cite{DagmarBruss}. We find the power of any given local channel for…

Quantum Physics · Physics 2015-06-12 Tahere Abad , Vahid Karimipour , Laleh Memarzadeh

This article is an introduction to quant-ph/0302092. We propose to quantify how "quantum" a set of quantum states is. The quantumness of a set is the worst-case difficulty of transmitting the states through a classical communication…

Quantum Physics · Physics 2007-05-23 Christopher A. Fuchs , Masahide Sasaki

Distinguishable and non-distinguishable quantum states are fundamental resources in quantum mechanics and quantum technologies. Interactions with the environment often induce decoherence, impacting both the distinguishability and…

Quantum Physics · Physics 2026-04-28 Kai Liu , Deguang Han

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

The ability to transfer coherent quantum information between systems is a fundamental component of quantum technologies and leads to coherent correlations within the global quantum process. However correlation structures in quantum channels…

Quantum Physics · Physics 2022-05-03 Matthew Girling , Cristina Cirstoiu , David Jennings

Various measures have been suggested recently for quantifying the coherence of a quantum state with respect to a given basis. We first use two of these, the l_1-norm and relative entropy measures, to investigate tradeoffs between the…

Quantum Physics · Physics 2015-10-08 Shuming Cheng , Michael J. W. Hall

By using the Choi-Jamio{\l}kowski isomorphism, we propose a well-defined coherence measure of quantum channels based on the generalized $\alpha$-$z$-relative R\'{e}nyi entropy. In addition, we present an alternative coherence measure of…

Quantum Physics · Physics 2025-06-13 Jiaorui Fan , Zhaoqi Wu , Shao-Ming Fei

The efficiency of parameter estimation of quantum channels is studied in this paper. We introduce the concept of programmable parameters to the theory of estimation. It is found that programmable parameters obey the standard quantum limit…

Quantum Physics · Physics 2010-03-17 Zhengfeng Ji , Guoming Wang , Runyao Duan , Yuan Feng , Mingsheng Ying

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

The reliability function gives the rate of exponential convergence to zero of the error probability in a communication channel. In this paper bounds for the reliability function of a quantum pure state channel are given, reminiscent of the…

Quantum Physics · Physics 2008-02-03 M. V. Burnashev , A. S. Holevo

Quantum coherence is an essential resource for quantum information processing and various quantitative measures of it have been introduced. However, the interconnections between these measures are not yet understood properly. Here, using a…

Quantum Physics · Physics 2022-06-07 Sandeep Mishra , Kishore Thapliyal , Anirban Pathak , Anu Venugopalan

A quantum channel is sufficient with respect to a set of input states if it can be reversed on this set. In the approximate version, the input states can be recovered within an error bounded by the decrease of the relative entropy under the…

Quantum Physics · Physics 2024-11-14 Anna Jenčová

We present a scalable method for learning local quantum channels using local expectation values measured on a single state -- their steady state. Our method is inspired by the algorithms for learning local Hamiltonians from their ground…

Quantum Physics · Physics 2024-07-12 Yigal Ilin , Itai Arad

We propose a method to detect lower bounds to quantum capacities of a noisy quantum communication channel by means of few measurements. The method is easily implementable and does not require any knowledge about the channel. We test its…

Quantum Physics · Physics 2016-04-12 Chiara Macchiavello , Massimiliano F. Sacchi

In this paper we study quantum communication channels with correlated noise effects, i.e., quantum channels with memory. We derive a model for correlated noise channels that includes a channel memory state. We examine the case where the…

Quantum Physics · Physics 2009-11-10 Garry Bowen , Stefano Mancini

By preparing an input state and measuring an observable for the output state, we can measure a quantum channel. Following the formulation given by Xiao et al., we study an uncertainty relation for ancilla-free measurements of random unitary…

Quantum Physics · Physics 2023-03-22 Taihei Kimoto , Takayuki Miyadera

In this paper, we introduce the framework for quantifying the imaginarity of quantum channels. Besides, an alternative framework is given together to simplify the process of verifying the condition. We present three imaginarity measures of…

Quantum Physics · Physics 2025-02-25 Xiangyu Chen , Qiang Lei

The inherent connection between noise and disturbance is one of the most fundamental features of quantum measurements. In the two well-known extreme cases a measurement either makes no disturbance but then has to be totally noisy or is as…

Quantum Physics · Physics 2014-01-08 Teiko Heinosaari , Takayuki Miyadera

The zero-error capacity of quantum channels was defined as the least upper bound of rates at which classical information can be transmitted through a quantum channel with probability of error equal to zero. This paper investigates some…

Quantum Physics · Physics 2007-05-23 Rex A C Medeiros , Romain Alleaume , Gerard Cohen , Francisco M. de Assis