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Computing and Communications Theory

We perform research in mathematics, physics, computer science, and measurement science necessary to enable the development and analysis of current and future computing and communications systems.

The group applies expertise in mathematical subdisciplines such as combinatorics, graph theory, network science, operations research, optimization, discrete nonlinear dynamics, computational geometry, quantum mechanics, and information theory.  Researchers apply their knowledge and skills in areas such as the fundamental models of physics, chemistry, biology, and information systems, complex systems analysis, pattern recognition, and quantum computing and communications.  In collaboration with NIST and outside scientists, the group develops, analyzes, and applies related mathematical methods and tools for critical problems of measurement science at NIST, and develops mathematical foundations for the measurement science of information systems.

News and Updates

Unity in the Photon Community

The creation and detection of single photons (the smallest units of light) has grown in a few decades from an experimental laboratory pursuit to an important

Projects and Programs

Quantum Communications and Networks

The Quantum Communication and Networks Project develops quantum devices and studies them for use in quantum communications and networking applications. Our goal


Entangled photon pair generation in an integrated SiC platform

Anouar Rahmouni, Lijun Ma, Ruixuan Wang, Jingwei Li, Xiao Tang, Thomas Gerrits, Qing Li, Oliver T. Slattery
Entanglement plays a vital role in quantum information processing. Owing to its unique material properties, silicon carbide recently emerged as a promising

Metropolitan-scale Entanglement Distribution, with Co-existing Quantum and Classical Signals in a single fiber

Anouar Rahmouni, Paulina Kuo, Ya-Shian Li-Baboud, Ivan Burenkov, Yicheng Shi, Jabir Marakkarakath Vadakkepurayil, Nijil Lal Cheriya Koyyottummal, Dileep Reddy, Mheni Merzouki, Lijun Ma, Abdella Battou, Sergey Polyakov, Oliver T. Slattery, Thomas Gerrits
The development of prototype metropolitan-scale quantum networks is underway and entails transmitting quantum information via single photons through deployed

Towards a resolution of the spin alignment problem

Mohammad Alhejji, Emanuel Knill
Consider the problem of minimizing the entropy of a mixture of states by choosing each state subject to constraints. If the spectrum of each state is fixed, we


Network Modeling Software

This software is a set of NetworkX additions for the creation of graphs to model networks. Graphicality Testing -- This is a set of routines for testing if a