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Related papers: Quantum Channel Capacity of Very Noisy Channels

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We give a short proof that the coherent information is an achievable rate for the transmission of quantum information through a noisy quantum channel. Our method is to produce random codes by performing a unitarily covariant projective…

Quantum Physics · Physics 2016-11-17 Patrick Hayden , Michal Horodecki , Andreas Winter , Jon Yard

Recent progress in quantum computing has enabled systems with tens of reliable logical qubits, built from thousands of noisy physical qubits. However, many impactful applications demand quantum computations with millions of logical qubits,…

Quantum Physics · Physics 2026-05-26 Daiki Komoto , Kenta Kasai

We study the super dense coding capacity in the presence of quantum channels with correlated noise. We investigate both the cases of unitary and non-unitary encoding. Pauli channels for arbitrary dimensions are treated explicitly. The super…

Quantum Physics · Physics 2011-10-07 Zahra Shadman , Hermann Kampermann , Chiara Macchiavello , Dagmar Bruß

A striking feature of quantum error correcting codes is that they can sometimes be used to correct more errors than they can uniquely identify. Such degenerate codes have long been known, but have remained poorly understood. We provide a…

Quantum Physics · Physics 2007-05-23 Graeme Smith , John A. Smolin

Noise in quantum computing is countered with quantum error correction. Achieving optimal performance will require tailoring codes and decoding algorithms to account for features of realistic noise, such as the common situation where the…

Quantum Physics · Physics 2020-04-02 David K. Tuckett , Stephen D. Bartlett , Steven T. Flammia , Benjamin J. Brown

We apply a dynamical systems approach to concatenation of quantum error correcting codes, extending and generalizing the results of Rahn et al. [1] to both diagonal and nondiagonal channels. Our point of view is global: instead of focusing…

Quantum Physics · Physics 2007-05-23 Jesse Fern , Julia Kempe , Slobodan Simic , Shankar Sastry

A rateless coding scheme transmits incrementally more and more coded bits over an unknown channel until all the information bits are decoded reliably by the receiver. We propose a new rateless coding scheme based on polar codes, and we show…

Information Theory · Computer Science 2015-08-14 Bin Li , David Tse , Kai Chen , Hui Shen

Quantum error correction methods use processing power to combat noise. The noise level which can be tolerated in a fault-tolerant method is therefore a function of the computational resources available, especially the size of computer and…

Quantum Physics · Physics 2015-06-26 Andrew Steane

We present a nonintrusive method for reliably estimating the noise level during quantum computation and quantum communication protected by quantum error-correcting codes. As preprocessing of quantum error correction, our scheme estimates…

Quantum Physics · Physics 2014-05-27 Yuichiro Fujiwara

The weak converse coding theorems have been proved for the quantum source and channel. The results give the lower bound for capacity of source and the upper bound for capacity of channel. The monotonicity of mutual quantum information have…

Quantum Physics · Physics 2008-02-03 A. E. Allahverdyan , D. B. Saakian

We introduce a convergent iterative algorithm for finding the optimal coding and decoding operations for an arbitrary noisy quantum channel. This algorithm does not require any error syndrome to be corrected completely, and hence also finds…

Quantum Physics · Physics 2007-07-26 M. Reimpell , R. F. Werner

We construct families of high performance quantum amplitude damping codes. All of our codes are nonadditive and most modestly outperform the best possible additive codes in terms of encoded dimension. One family is built from nonlinear…

Quantum Physics · Physics 2009-07-30 Peter W. Shor , Graeme Smith , John A. Smolin , Bei Zeng

The capacity of noisy quantum channels characterizes the highest rate at which information can be reliably transmitted and it is therefore of practical as well as fundamental importance. Capacities of classical channels are computed using…

Quantum Physics · Physics 2021-07-02 Navneeth Ramakrishnan , Raban Iten , Volkher B. Scholz , Mario Berta

This paper presents an analysis of spinal codes, a class of rateless codes proposed recently. We prove that spinal codes achieve Shannon capacity for the binary symmetric channel (BSC) and the additive white Gaussian noise (AWGN) channel…

Information Theory · Computer Science 2012-06-05 Hari Balakrishnan , Peter Iannucci , Jonathan Perry , Devavrat Shah

I make a rough estimate of the accuracy threshold for fault tolerant quantum computing with concatenated codes. First I consider only gate errors and use the depolarizing channel error model. I will follow P.Shor (quant-ph/9505011) for…

Quantum Physics · Physics 2008-02-03 Christof Zalka

Consider a pair of terminals connected by two independent additive white Gaussian noise channels, and limited by individual power constraints. The first terminal would like to reliably send information to the second terminal, within a given…

Information Theory · Computer Science 2014-12-16 Assaf Ben-Yishai , Ofer Shayevitz

We derive upper bounds on the rate of transmission of classical information over quantum channels by block codes with a given blocklength and error probability, for both entanglement-assisted and unassisted codes, in terms of a unifying…

Quantum Physics · Physics 2016-01-01 William Matthews , Stephanie Wehner

We present a two-step decoder for the parity code and evaluate its performance in code-capacity and faulty-measurement settings. For noiseless measurements, we find that the decoding problem can be reduced to a series of repetition codes…

A central challenge in quantum error correction is identifying powerful quantum codes tailored to specific hardware and determining their error thresholds above which quantum information is unprotected. This problem is hard because we…

Quantum Physics · Physics 2026-01-07 Gaurav Gyawali , Henry Shackleton , Zhu-Xi Luo , Michael Lawler

We consider communication over a noisy network under randomized linear network coding. Possible error mechanism include node- or link- failures, Byzantine behavior of nodes, or an over-estimate of the network min-cut. Building on the work…

Information Theory · Computer Science 2007-11-27 Andrea Montanari , Ruediger Urbanke