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Quantum state exclusion is an operational task with application to ontological interpretations of quantum states. In such a task, one is given a system whose state is randomly selected from a finite set, and the goal is to identify a state…

Quantum Physics · Physics 2026-03-25 Kaiyuan Ji , Hemant K. Mishra , Milán Mosonyi , Mark M. Wilde

The concept of multiple particle interference is discussed, using insights provided by the classical theory of error correcting codes. This leads to a discussion of error correction in a quantum communication channel or a quantum computer.…

Quantum Physics · Physics 2009-10-30 Andrew Steane

A new channel coding approach was proposed in [1] for random multiple access communication over the discrete-time memoryless channel. The coding approach allows users to choose their communication rates independently without sharing the…

Information Theory · Computer Science 2016-11-15 Zheng Wang , Jie Luo

Fault-tolerant schemes can use error correction to make a quantum computation arbitrarily ac- curate, provided that errors per physical component are smaller than a certain threshold and in- dependent of the computer size. However in…

Quantum Physics · Physics 2022-02-24 Marco Fellous-Asiani , Jing Hao Chai , Robert S. Whitney , Alexia Auffèves , Hui Khoon Ng

By exploiting a generalization of recent results on environment-assisted channel correction, we show that, whenever a quantum system undergoes a channel realized as an interaction with a probe, the more efficiently the information about the…

Quantum Physics · Physics 2007-10-29 Francesco Buscemi

We investigate minimum output (R\'enyi) entropy of qubit channels and unital quantum channels. We obtain an exact formula for the minimum output entropy of qubit channels, and bounds for unital quantum channels. Interestingly, our bounds…

Quantum Physics · Physics 2019-12-02 Motohisa Fukuda , Gilad Gour

We analyze the problem of zero-error communication through timing channels that can be interpreted as discrete-time queues with bounded waiting times. The channel model includes the following assumptions: 1) Time is slotted, 2) at most $ N…

Information Theory · Computer Science 2020-08-13 Mladen Kovačević , Petar Popovski

For every p in (0,1/2), we give an explicit construction of binary codes of rate approaching "capacity" 1-H(p) that enable reliable communication in the presence of worst-case additive errors}, caused by a channel oblivious to the codeword…

Information Theory · Computer Science 2010-05-04 Venkatesan Guruswami , Adam Smith

Thermal attenuator channels model the decoherence of quantum systems interacting with a thermal bath, e.g., a two-level system subject to thermal noise and an electromagnetic signal travelling through a fiber or in free-space. Hence…

Quantum Physics · Physics 2018-12-12 Matteo Rosati , Andrea Mari , Vittorio Giovannetti

We investigate state estimation of linear systems over channels having a finite state not known by the transmitter or receiver. We show that similar to memoryless channels, zero-error capacity is the right figure of merit for achieving…

Systems and Control · Electrical Eng. & Systems 2021-10-06 Amir Saberi , Farhad Farokhi , Girish N. Nair

The optimal rate at which information can be sent through a quantum channel when the transmitted signal must simultaneously carry some minimum amount of energy is characterized. To do so, we introduce the quantum-classical analogue of the…

Quantum Physics · Physics 2025-01-10 Bishal Kumar Das , Lav R. Varshney , Vaibhav Madhok

Losses in quantum communication lines severely affect the rates of reliable information transmission and are usually considered to be state-independent. However, the loss probability does depend on the system state in general, with the…

Quantum Physics · Physics 2021-06-01 Sergey N. Filippov

A unified approach to prove the converses for the quantum channel capacity theorems is presented. These converses include the strong converse theorems for classical or quantum information transfer with error exponents and novel explicit…

Quantum Physics · Physics 2013-03-14 Naresh Sharma , Naqueeb Ahmad Warsi

We find the maximum rate achievable in the private communication over a bosonic quantum channel with a fully Gaussian protocol based on optimal single-mode Gaussian measurements. This rate establishes a lower bound on the secret rate…

Quantum Physics · Physics 2025-12-18 Giuseppe Ortolano , Stefano Pirandola , Leonardo Banchi

As a class of state-dependent channels, Markov channels have been long studied in information theory for characterizing the feedback capacity and error exponent. This paper studies a more general variant of such channels where the state…

Information Theory · Computer Science 2022-02-22 Mohsen Heidari , Achilleas Anastasopoulos , S. Sandeep Pradhan

In the shallow sub-threshold regime, fault-tolerant quantum computation requires a tremendous amount of qubits. In this paper, we study the error correction in the deep sub-threshold regime. We estimate the physical error rate for achieving…

Quantum Physics · Physics 2020-09-22 Dawei Jiao , Ying Li

Fault tolerant quantum error correction (QEC) networks are studied by a combination of numerical and approximate analytical treatments. The probability of failure of the recovery operation is calculated for a variety of CSS codes, including…

Quantum Physics · Physics 2009-11-07 Andrew M. Steane

Communication channels are said to be underspread if their coherence time is greater than their delay spread. In such cases it can be shown that in the infinite bandwidth limit the information capacity tends to that of a channel with…

Information Theory · Computer Science 2014-06-24 Steven Herbert , Ian Wassell , Tian-Hong Loh

To well understand the behavior of quantum error correction codes (QECC) in noise processes, we need to obtain explicit coding maps for QECC. Due to extraordinary amount of computational labor that they entails, explicit coding maps are a…

Quantum Physics · Physics 2022-03-04 Chaobin Liu

As shown by M\'edard, the capacity of fading channels with imperfect channel-state information (CSI) can be lower-bounded by assuming a Gaussian channel input $X$ with power $P$ and by upper-bounding the conditional entropy $h(X|Y,\hat{H})$…

Information Theory · Computer Science 2016-11-15 Adriano Pastore , Tobias Koch , Javier Rodríguez Fonollosa