297 research outputs found
Entanglement Availability Differentiation Service for the Quantum Internet
A fundamental concept of the quantum Internet is quantum entanglement. In a
quantum Internet scenario where the legal users of the network have different
priority levels or where a differentiation of entanglement availability between
the users is a necessity, an entanglement availability service is essential.
Here we define the entanglement availability differentiation (EAD) service for
the quantum Internet. In the proposed EAD framework, the differentiation is
either made in the amount of entanglement with respect to the relative entropy
of entanglement associated with the legal users, or in the time domain with
respect to the amount of time that is required to establish a maximally
entangled system between the legal parties. The framework provides an efficient
and easily-implementable solution for the differentiation of entanglement
availability in experimental quantum networking scenarios.Comment: 18 pages, Journal-ref: Scientific Report
A Tight Bound for Probability of Error for Quantum Counting Based Multiuser Detection
Future wired and wireless communication systems will employ pure or combined
Code Division Multiple Access (CDMA) technique, such as in the European 3G
mobile UMTS or Power Line Telecommunication system, but also several 4G
proposal includes e.g. multi carrier (MC) CDMA. Former examinations carried out
the drawbacks of single user detectors (SUD), which are widely employed in
narrowband IS-95 CDMA systems, and forced to develop suitable multiuser
detection schemes to increase the efficiency against interference. However, at
this moment there are only suboptimal solutions available because of the rather
high complexity of optimal detectors. One of the possible receiver technologies
can be the quantum assisted computing devices which allows high level
parallelism in computation. The first commercial devices are estimated for the
next years, which meets the advert of 3G and 4G systems. In this paper we
analyze the error probability and give tight bounds in a static and dynamically
changing environment for a novel quantum computation based Quantum Multiuser
detection (QMUD) algorithm, employing quantum counting algorithm, which
provides optimal solution.Comment: presented at IEEE ISIT 2002, 7 pages, 2 figure
Private Quantum Coding for Quantum Relay Networks
The relay encoder is an unreliable probabilistic device which is aimed at
helping the communication between the sender and the receiver. In this work we
show that in the quantum setting the probabilistic behavior can be completely
eliminated. We also show how to combine quantum polar encoding with
superactivation-assistance in order to achieve reliable and capacity-achieving
private communication over noisy quantum relay channels.Comment: 15 pages, 3 figures, Journal-ref: Lecture Notes in Computer Science,
Vol. 7479, pp. 239-250. Springer-Verlag, 2012, presented in part at the 11th
Intl. Conference on Quantum Communication, Measurement and Computing
(QCMC2012), v2: minor formatting change
Topology Adaption for the Quantum Internet
In the quantum repeater networks of the quantum Internet, the varying
stability of entangled quantum links makes dynamic topology adaption an
emerging issue. Here we define an efficient topology adaption method for
quantum repeater networks. The model assumes the random failures of entangled
links and several parallel demands from legal users. The shortest path defines
a set of entangled links for which the probability of stability is above a
critical threshold. The scheme is utilized in a base-graph of the overlay
quantum network to provide an efficient shortest path selection for the demands
of all users of the network. We study the problem of entanglement assignment in
a quantum repeater network, prove its computational complexity, and show an
optimization procedure. The results are particularly convenient for future
quantum networking, quantum-Internet, and experimental long-distance quantum
communications.Comment: 17 pages, Journal-ref: Quant. Inf. Proc. (2018
- …