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Related papers: Unbounded Communication Power of a Qubit

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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

Quantum theory is in principle compatible with scenarios where physical processes occur in an indefinite order, potentially yielding advantages in a broad range of information processing tasks. However, advantages in communication, the most…

Quantum Physics · Physics 2026-03-26 Xuanqiang Zhao , Benchi Zhao , Cyril Branciard , Giulio Chiribella

Quantum catalysts enable transformations that otherwise would be forbidden, offering a pathway to surpass conventional limits in quantum information processing. Among them, embezzling catalysts stand out for achieving near-perfect…

Quantum Physics · Physics 2025-10-31 Haitao Ma , Yantong Li , Yingchun Kang , Bing Yu , Junjing Xing , Zhaobing Fan , Yunlong Xiao

We consider quantum and private communications assisted by repeaters, from the basic scenario of a single repeater chain to the general case of an arbitrarily-complex quantum network, where systems may be routed through single or multiple…

Quantum Physics · Physics 2017-08-17 Stefano Pirandola

In STOC 1999, Raz presented a (partial) function for which there is a quantum protocol communicating only $O(\log n)$ qubits, but for which any classical (randomized, bounded-error) protocol requires $\poly(n)$ bits of communication. That…

Computational Complexity · Computer Science 2010-09-21 Bo'az Klartag , Oded Regev

All communication channels are at bottom quantum mechanical. Quantum mechanics contributes both obstacles to communication in the form of noise, and opportunities in the use of intrinsically quantum representations for information. This…

Quantum Physics · Physics 2007-05-23 Seth Lloyd

Random access code (RAC), a primitive for many information processing protocols, enables one party to encode n-bit string into one bit of message such that another party can retrieve partial information of that string. We introduce the…

Quantum Physics · Physics 2020-02-28 Debashis Saha , Jakub J. Borkala

This paper studies the gap between quantum one-way communication complexity $Q(f)$ and its classical counterpart $C(f)$, under the {\em unbounded-error} setting, i.e., it is enough that the success probability is strictly greater than 1/2.…

Quantum Physics · Physics 2007-09-18 Kazuo Iwama , Harumichi Nishimura , Rudy Raymond , Shigeru Yamashita

Communication complexity is a fundamental aspect of information science, concerned with the amount of communication required to solve a problem distributed among multiple parties. The standard quantification of one-way communication…

Quantum Physics · Physics 2024-12-25 Satyaki Manna , Anubhav Chaturvedi , Debashis Saha

Quantum measurement has conventionally been regarded as the final step in quantum information processing, which is essential for reading out the processed information but collapses the quantum state into a classical state. However, recent…

Quantum Physics · Physics 2024-02-02 Dongjin Lee , Beni Yoshida

Quantum information theory predicts that when the transmission resource is doubled in quantum channels, the amount of information transmitted can be increased more than twice by quantum channel coding technique, whereas the increase is at…

Quantum Physics · Physics 2009-11-10 M. Takeoka , M. Fujiwara , J. Mizuno , M. Sasaki

Measurement incompatibility stipulates the existence of quantum measurements that cannot be carried out simultaneously on single systems. We show that the set of input-output probabilities obtained from d-dimensional classical systems…

Quantum Physics · Physics 2023-06-13 Debashis Saha , Debarshi Das , Arun Kumar Das , Bihalan Bhattacharya , A. S. Majumdar

We describe a general quantum receiver protocol that maps laser-light-modulated classical communications signals into quantum processors for decoding with quantum logic. The quantum logic enables joint quantum measurements over a codeword…

Quantum Physics · Physics 2026-03-16 Kelly Werker Smith , Don Boroson , Saikat Guha , Johannes Borregaard

A longstanding goal in quantum information science is to demonstrate quantum computations that cannot be feasibly reproduced on a classical computer. Such demonstrations mark major milestones: they showcase fine control over quantum systems…

The quantum enhancement of success probability in the Random Access Code (RAC) protocols remains unexplored from two important perspectives. First, the use of entanglement between two co-measurable degrees of freedom of a single particle…

Quantum Physics · Physics 2026-05-19 Nilaj Saha , Sumit Mukherjee , Dipankar Home

The accessible information quantifies the amount of classical information that can be extracted from an ensemble of quantum states. Analogously, the informational power quantifies the amount of classical information that can be extracted by…

Quantum Physics · Physics 2014-08-06 Michele Dall'Arno , Francesco Buscemi , Masanao Ozawa

We investigate the information provided about a specified distributed apparatus of n units in the measurement of a quantum state. It is shown that, in contrast to such measurement of a classical state, which is bounded by log (n+1) bits,…

Quantum Physics · Physics 2014-11-18 Subhash Kak

Quantum information processing is the emerging field that defines and realizes computing devices that make use of quantum mechanical principles, like the superposition principle, entanglement, and interference. In this review we study the…

Quantum Physics · Physics 2015-05-13 Harry Buhrman , Richard Cleve , Serge Massar , Ronald de Wolf

Extension of point-to-point communication model to the realm of multi-node configurations finds a plethora of applications in internet and telecommunication networks. Here, we establish a novel advantage of quantum communication in a…

One of the most intriguing facts about communication using quantum states is that these states cannot be used to transmit more classical bits than the number of qubits used, yet there are ways of conveying information with exponentially…

Quantum Physics · Physics 2007-05-23 Ashwin Nayak , Amnon Ta-Shma , David Zuckerman