2,998 research outputs found
Quantum repeaters with individual rare-earth ions at telecommunication wavelengths
We present a quantum repeater scheme that is based on individual erbium and
europium ions. Erbium ions are attractive because they emit photons at
telecommunication wavelength, while europium ions offer exceptional spin
coherence for long-term storage. Entanglement between distant erbium ions is
created by photon detection. The photon emission rate of each erbium ion is
enhanced by a microcavity with high Purcell factor, as has recently been
demonstrated. Entanglement is then transferred to nearby europium ions for
storage. Gate operations between nearby ions are performed using dynamically
controlled electric-dipole coupling. These gate operations allow entanglement
swapping to be employed in order to extend the distance over which entanglement
is distributed. The deterministic character of the gate operations allows
improved entanglement distribution rates in comparison to atomic ensemble-based
protocols. We also propose an approach that utilizes multiplexing in order to
enhance the entanglement distribution rate.Comment: 13 pages, 4 figure
Recursive quantum repeater networks
Internet-scale quantum repeater networks will be heterogeneous in physical
technology, repeater functionality, and management. The classical control
necessary to use the network will therefore face similar issues as Internet
data transmission. Many scalability and management problems that arose during
the development of the Internet might have been solved in a more uniform
fashion, improving flexibility and reducing redundant engineering effort.
Quantum repeater network development is currently at the stage where we risk
similar duplication when separate systems are combined. We propose a unifying
framework that can be used with all existing repeater designs. We introduce the
notion of a Quantum Recursive Network Architecture, developed from the emerging
classical concept of 'recursive networks', extending recursive mechanisms from
a focus on data forwarding to a more general distributed computing request
framework. Recursion abstracts independent transit networks as single relay
nodes, unifies software layering, and virtualizes the addresses of resources to
improve information hiding and resource management. Our architecture is useful
for building arbitrary distributed states, including fundamental distributed
states such as Bell pairs and GHZ, W, and cluster states.Comment: 14 page
Developing an Efficient DMCIS with Next-Generation Wireless Networks
The impact of extreme events across the globe is extraordinary which
continues to handicap the advancement of the struggling developing societies
and threatens most of the industrialized countries in the globe. Various fields
of Information and Communication Technology have widely been used for efficient
disaster management; but only to a limited extent though, there is a tremendous
potential for increasing efficiency and effectiveness in coping with disasters
with the utilization of emerging wireless network technologies. Early warning,
response to the particular situation and proper recovery are among the main
focuses of an efficient disaster management system today. Considering these
aspects, in this paper we propose a framework for developing an efficient
Disaster Management Communications and Information System (DMCIS) which is
basically benefited by the exploitation of the emerging wireless network
technologies combined with other networking and data processing technologies.Comment: 6 page
A Secure Lightweight Approach of Node Membership Verification in Dense HDSN
In this paper, we consider a particular type of deployment scenario of a
distributed sensor network (DSN), where sensors of different types and
categories are densely deployed in the same target area. In this network, the
sensors are associated with different groups, based on their functional types
and after deployment they collaborate with one another in the same group for
doing any assigned task for that particular group. We term this sort of DSN as
a heterogeneous distributed sensor network (HDSN). Considering this scenario,
we propose a secure membership verification mechanism using one-way accumulator
(OWA) which ensures that, before collaborating for a particular task, any pair
of nodes in the same deployment group can verify each other-s legitimacy of
membership. Our scheme also supports addition and deletion of members (nodes)
in a particular group in the HDSN. Our analysis shows that, the proposed scheme
could work well in conjunction with other security mechanisms for sensor
networks and is very effective to resist any adversary-s attempt to be included
in a legitimate group in the network.Comment: 6 page
Building accurate radio environment maps from multi-fidelity spectrum sensing data
In cognitive wireless networks, active monitoring of the wireless environment is often performed through advanced spectrum sensing and network sniffing. This leads to a set of spatially distributed measurements which are collected from different sensing devices. Nowadays, several interpolation methods (e.g., Kriging) are available and can be used to combine these measurements into a single globally accurate radio environment map that covers a certain geographical area. However, the calibration of multi-fidelity measurements from heterogeneous sensing devices, and the integration into a map is a challenging problem. In this paper, the auto-regressive co-Kriging model is proposed as a novel solution. The algorithm is applied to model measurements which are collected in a heterogeneous wireless testbed environment, and the effectiveness of the new methodology is validated
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