The patent badge is an abbreviated version of the USPTO patent document. The patent badge does contain a link to the full patent document.
The patent badge is an abbreviated version of the USPTO patent document. The patent badge covers the following: Patent number, Date patent was issued, Date patent was filed, Title of the patent, Applicant, Inventor, Assignee, Attorney firm, Primary examiner, Assistant examiner, CPCs, and Abstract. The patent badge does contain a link to the full patent document (in Adobe Acrobat format, aka pdf). To download or print any patent click here.
Patent No.:
Date of Patent:
Sep. 01, 2009
Filed:
Jul. 28, 2006
Alexei Trifonov, Boston, MA (US);
Alexei Trifonov, Boston, MA (US);
MagiQ Technologies, Inc., New York, NY (US);
Abstract
The quantum key distribution (QKD) systems () of the invention includes first and second QKD stations (Alice and Bob) according to the present invention, wherein either one or both QKD stations include fast optical switches (). Each fast optical switch is respectively optically coupled to two different round-trip optical paths (OPand OPat Alice, OPand OPat Bob) of different length that define respective optical path differences OPDand OPD, wherein OPD=OPD. By switching the fast optical switches using timed switching signals (S-Sat Alice, S-Sat Bob) from their corresponding controllers (CA at Alice, CB at Bob), the quantum signals—which can be single-photon or weak-coherent pulses—can be generated from a single optical pulse (), randomly selectively encoded while traversing the optical paths in Alice and Bob, and then interfered and measured (detected) at Bob. The QKD system has less loss as compared to conventional fiber-based QKD systems because it omits at least some of the beamsplitters in conventional QKD systems.