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Related papers: Postselected communication over quantum channels

200 papers

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

Sending quantum information reliably over long distances is a central challenge in quantum technology in general, and in quantum optics in particular, since most quantum communication relies on optical fibres or free-space links. Here, we…

Quantum Physics · Physics 2026-02-27 Tobias Rippchen , Ludovico Lami , Gerardo Adesso , Mario Berta

We introduce a new analysis technique to derive a single-letter upper bound on the mismatch capacity of a stationary, single-user, memoryless channel with a decoding metric $q$. Our bound is obtained by considering a multicast transmission…

Information Theory · Computer Science 2021-03-29 Anelia Somekh-Baruch

We introduce a new quantum decoder based on a variant of the pretty good measurement, but defined via an alternative matrix quotient. We use this decoder to show new lower bounds on the error exponent both in the one-shot and asymptotic…

Quantum Physics · Physics 2025-07-29 Salman Beigi , Marco Tomamichel

We report an experimental demonstration of effective entanglement in a prepare&measure type of quantum key distribution protocol. Coherent polarization states and heterodyne measurement to characterize the transmitted quantum states are…

Quantum Physics · Physics 2009-11-13 S. Lorenz , J. Rigas , M. Heid , U. L. Andersen , N. Lütkenhaus , G. Leuchs

We study the power of measurements implementable with local quantum operations and classical communication (or LOCC measurements for short) in the setting of quantum channel discrimination. More precisely, we consider discrimination…

Quantum Physics · Physics 2011-03-16 William Matthews , Marco Piani , John Watrous

One of the main figures of merit for quantum memories and quantum communication devices is their quantum capacity. It has been studied for arbitrary kinds of quantum channels, but its practical estimation has so far been limited to devices…

Quantum Physics · Physics 2018-05-16 Corsin Pfister , M. Adriaan Rol , Atul Mantri , Marco Tomamichel , Stephanie Wehner

We begin this thesis by expanding the technique of teleportation simulation, which adds noise to the entangled resource state to mimic channel effects. By introducing classical noise in the communication step, we show it is possible to…

Quantum Physics · Physics 2019-04-29 Thomas Cope

We investigate the problem of information theoretically secure communication in a line network with erasure channels and state feedback. We consider a spectrum of cases for the private randomness that intermediate nodes can generate,…

Information Theory · Computer Science 2014-07-09 Athanasios Papadopoulos , Laszlo Czap , Christina Fragouli

We present an upper bound for the quantum channel capacity that is both additive and convex. Our bound can be interpreted as the capacity of a channel for high-fidelity quantum communication when assisted by a family of channels that have…

Quantum Physics · Physics 2008-08-28 Graeme Smith , John A. Smolin , Andreas Winter

Capacity of a quantum channel characterizes the limits of reliable communication through a noisy quantum channel. This fundamental information theoretic question is very well studied specially in the setting of many independent uses of the…

Quantum Physics · Physics 2019-03-19 Anurag Anshu , Rahul Jain , Naqueeb Ahmad Warsi

Postselected quantum computation is distinguished from regular quantum computation by accepting the output only if measurement outcomes satisfy predetermined conditions. The output must be accepted with nonzero probability. Methods for…

Quantum Physics · Physics 2007-05-23 E. Knill

Secret-key distillation from quantum states and channels is a central task of interest in quantum information theory, as it facilitates private communication over a quantum network. Here, we study the task of secret-key distillation from…

Quantum Physics · Physics 2025-06-16 Vishal Singh , Mark M. Wilde

We show that weakly entangled states can improve communication over a qubit channel using only separate, interference-free, measurements of individual photons. We introduce a communication task corresponding to the cryptographic primitive…

A scenario involving a source, a channel, and a destination, where the destination is interested in {\em both} reliably reconstructing the message transmitted by the source and estimating with a fidelity criterion the state of the channel,…

Information Theory · Computer Science 2011-08-30 Wenyi Zhang , Satish Vedantam , Urbashi Mitra

Using a technique based on quantum teleportation, we simplify the most general adaptive protocols for key distribution, entanglement distillation and quantum communication over a wide class of quantum channels in arbitrary dimension. Thanks…

Quantum Physics · Physics 2018-05-16 Stefano Pirandola , Riccardo Laurenza

The unique and often-weird properties of quantum mechanics allow an information carrier to propagate through multiple trajectories of quantum channels simultaneously. This ultimately leads us to quantum trajectories with an indefinite…

Quantum Physics · Physics 2021-10-22 Daryus Chandra , Marcello Caleffi , Angela Sara Cacciapuoti

This paper presents generalized channel coding theorems for a time-slotted distributed communication system where a transmitter-receiver pair is communicating in parallel with other transmitters. Assume that the channel code of each…

Information Theory · Computer Science 2016-11-15 Jie Luo

A major challenge of today's quantum communication systems lies in the transmission of quantum information with high rates over long distances in the presence of unavoidable losses. Thereby the achievable quantum communication rate is…

Quantum Physics · Physics 2012-08-22 Andreas Christ , Cosmo Lupo , Christine Silberhorn

We show that entanglement is a useful resource to enhance the mutual information of the depolarizing channel when the noise on consecutive uses of the channel has some partial correlations. We obtain a threshold in the degree of memory,…

Quantum Physics · Physics 2009-11-07 Chiara Macchiavello , G. Massimo Palma