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Information Technology Laboratory /Applied and Computational Mathematics Division

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

NIST chip containing a single-photon detector made of superconducting nanowires. Four chips like this were used in the experiment that entangled three photons.

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

Image depiction of: To connect two nodes operating at different wavelengths, there are generally two strategies: (1) use quantum frequency conversion or quantum transduction to convert the wavelength of the photon emitted by one node to the wavelength of the second node, or (2) connect the two nodes using an entangled photon pair source whose two photons have wavelengths that match the two nodes. Both techniques involve nonlinear optics.

Nonlinear Optics for Quantum Information and Networking

Ongoing
Quantum networking and distributed quantum sensing will require photonic links (so called flying qubits) to connect nodes and enable scaling to larger distances and network sizes. An interconnect may consist of a photon going from one node to another where both nodes operate at the same wavelength

Quantum Communications and Networks

Ongoing
Key Components of Quantum Repeaters and Quantum Network Systems Single Photon Sources: An ideal single photon entangled pair source for a quantum repeater application should satisfy several conditions simultaneously. Since photons must interact efficiently with a quantum memory, the source must emit

Publications

100-km entanglement distribution with coexisting quantum and classical signals in a single fiber

Author(s)
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

Entangled photon pair generation in an integrated SiC platform

Author(s)
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

Synchronized source of indistinguishable photons for quantum networks

Author(s)
Nijil Lal Cheriya Koyyottummal, Ivan Burenkov, Ya-Shian Li-Baboud, Jabir Marakkarakath Vadakkepurayil, Paulina Kuo, Thomas Gerrits, Oliver T. Slattery, Sergey Polyakov
We present a source of indistinguishable photons at telecom wavelength, synchronized to an external clock, for the use in distributed quantum networks. We

Software

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

Awards