Advances in quantum cryptography for free-space communications

Quantum mechanics provides methods of encryption that are secure from eavesdropping attacks against the quantum channel. The National Institute of Standards and Technology (NIST; Gaithersburg, MD) has developed a high-speed quantum key distribution test bed incorporating both free-space and fiber systems.

In this video, Joshua Bienfang of NIST talks about the quantum cryptographic system that operates over a 1.5-kilometer free-space link on the NIST campus. These quantum communication systems rely on cryptographic key known to both the sender (Alice) and receiver (Bob). Transmitting at 1.25 gigahertz, any intrusion into the system would be detected by comparing data at the transmitting and receiving end.

Bienfang is a physicist in the Electron and Optical Physics Division at NIST, where he works on quantum cryptography.

Related publications:
Quantum key distribution at GHz transmission rates
Alessandro Restelli, Joshua C. Bienfang, Alan Mink, and Charles W. Clark
Proceedings of SPIE Volume 7236 (2009)

High speed quantum key distribution system supports one-time pad encryption of real-time video
Alan Mink, Xiao Tang, LiJun Ma, Tassos Nakassis, Barry Hershman, Joshua C. Bienfang, David Su, Ron Boisvert, Charles W. Clark, and Carl J. Williams
Proceedings of SPIE Volume 6244 (2006)

Category:

Science & Technology

Tags:

• Optics
• photonics
• SPIE
• lasers
• NIST
• Quantum Mechanics
• Communications

[Humanoya]

talk and talk and talk no demonstration very very very bad

[SPIETV]

@Humanoya Sorry you did not like the video. Unfortunately when we visited the lab, the system was not up and running. If you do a google search of Joshua Bienfang you can find some more info on the work being done in his lab. Thanks for watching.

[ZebaNaqvi]

Nice.. However it would be great if we could have a quick look at the way photons take from the pulsed laser to the detector at the receiver via the polarizers, beam splitters etc. as is there in my mind. May be they are using something else like phase encoding.

[Humanoya]

@SPIETV

thanks so much for the kind of explanation, excuse me if I have written in a way that made your work looked fake. My apology goes to everyone else who interprets wrong. and wish of course that this study will be success in the future