English
Related papers

Related papers: Memory effects in quantum channel discrimination

200 papers

Simulating the stochastic evolution of real quantities on a digital computer requires a trade-off between the precision to which these quantities are approximated, and the memory required to store them. The statistical accuracy of the…

Quantum Physics · Physics 2017-10-16 Andrew J. P. Garner , Qing Liu , Jayne Thompson , Vlatko Vedral , Mile Gu

We address the question of a quantum memory storage of quantum dynamics. In particular, we design an optimal protocol for $N\to 1$ probabilistic storage-and-retrieval of unitary channels on $d$-dimensional quantum systems. If we may access…

Quantum Physics · Physics 2019-05-08 Michal Sedlák , Alessandro Bisio , Mário Ziman

Any physical process can be represented as a quantum channel mapping an initial state to a final state. Hence it can be characterized from the point of view of communication theory, i.e., in terms of its ability to transfer information.…

Quantum Physics · Physics 2014-12-16 F. Caruso , V. Giovannetti , C. Lupo , S. Mancini

Quantum Channel Discrimination (QCD) presents a fundamental task in quantum information theory, with critical applications in quantum reading, illumination, data-readout and more. The extension to multiple quantum channel discrimination has…

Quantum Physics · Physics 2021-05-12 Cillian Harney , Leonardo Banchi , Stefano Pirandola

Quantum channels generally reduce the distinguishability of quantum states, limiting information transmission and processing. Previous work introduced a protocol capable of increasing the distinguishability of states after the action of a…

Quantum Physics · Physics 2026-05-08 Gabriel M. Arantes , Barbara Amaral , Nadja K. Bernardes

Quantum mechanics fundamentally forbids deterministic discrimination of quantum states and processes. However, the ability to optimally distinguish various classes of quantum data is an important primitive in quantum information science. In…

Quantum Physics · Physics 2021-03-10 Hongxiang Chen , Leonard Wossnig , Simone Severini , Hartmut Neven , Masoud Mohseni

We consider the problem of estimating an upper bound on the capacity of a memoryless channel with unknown channel law and continuous output alphabet. A novel data-driven algorithm is proposed that exploits the dual representation of…

Information Theory · Computer Science 2024-01-25 Christian Häger , Erik Agrell

What is the ultimate performance for discriminating two arbitrary quantum channels acting on a finite-dimensional Hilbert space? Here we address this basic question by deriving a general and fundamental lower bound. More precisely, we…

Quantum Physics · Physics 2019-08-09 Stefano Pirandola , Riccardo Laurenza , Cosmo Lupo , Jason L. Pereira

We study optimal rates for quantum communication over a single use of a channel, which itself can correspond to a finite number of uses of a channel with arbitrarily correlated noise. The corresponding capacity is often referred to as the…

Quantum Physics · Physics 2010-03-19 Francesco Buscemi , Nilanjana Datta

Quantum process tomography, the task of estimating an unknown quantum channel, is a central problem in quantum information theory. A long-standing open question is to determine the optimal number of uses of an unknown channel required to…

Quantum Physics · Physics 2026-01-19 Antonio Anna Mele , Lennart Bittel

A new protocol of the optical quantum memory based on the resonant interactions of the multi atomic system with a cavity light mode is proposed. The quantum memory is realized using a controllable inversion of the inhomogeneous broadening…

Quantum Physics · Physics 2007-05-23 S. A. Moiseev

Quantum networks, capable of transmitting arbitrary quantum states, provide a foundation for a wide range of quantum applications, including distributed quantum computing, distributed quantum sensing, and quantum communication. Photons are…

Quantum Physics · Physics 2025-08-28 Tian-Xiang Zhu , Xiao Liu , Zong-Quan Zhou , Chuan-Feng Li

We have proposed a scheme of the generation and preservation of two-qubit steady state quantum correlations through quantum channels where successive uses of the channels are correlated. Different types of noisy channels with memory, such…

Quantum Physics · Physics 2016-04-15 You-neng Guo , Mao-fa Fang , Guo-you Wang , Ke Zeng

A programmable quantum processor is a fundamental model of quantum computation. In this model, any quantum channel can be approximated by applying a fixed universal quantum operation onto an input state and a quantum `program' state, whose…

Quantum Physics · Physics 2020-05-20 Leonardo Banchi , Jason Pereira , Seth Lloyd , Stefano Pirandola

We examine the emergence of dynamical memory effects in quantum processes having indefinite time direction and causal order. In particular, we focus on the class of phase-covariant qubit channels, which encompasses some of the most…

Quantum Physics · Physics 2024-07-23 Göktuğ Karpat , Barış Çakmak

The quantum capacity of a memoryless channel is often used as a single figure of merit to characterize its ability to transmit quantum information coherently. The capacity determines the maximal rate at which we can code reliably over…

Quantum Physics · Physics 2016-05-10 Marco Tomamichel , Mario Berta , Joseph M. Renes

The channel polarization behavior of polar codes under noise with memory is investigated. By introducing a genie-aided channel model, we first show that the polarized subchannels still converge to extremal channels under the standard polar…

Information Theory · Computer Science 2025-09-12 Tianfu Qi , Jun Wang

The problem of dephasing channel discrimination is addressed for finite-dimensional systems. In particular, the optimization with respect to input states without energy constraint is solved analytically for qubit, qutrit and ququart.…

Quantum Physics · Physics 2023-10-25 Milajiguli Rexiti , Laleh Memarzadeh , Stefano Mancini

It is well known that for the discrimination of classical and quantum channels in the finite, non-asymptotic regime, adaptive strategies can give an advantage over non-adaptive strategies. However, Hayashi [IEEE Trans. Inf. Theory 55(8),…

Quantum Physics · Physics 2020-07-24 Mark M. Wilde , Mario Berta , Christoph Hirche , Eneet Kaur

With the aid of a quantum memory, the uncertainty about the measurement outcomes of two incompatible observables of a quantum system can be reduced. We investigate this measurement uncertainty bound by considering an additional quantum…

Quantum Physics · Physics 2013-02-15 Ming-Liang Hu , Heng Fan