International Journal of Optics

Polarization-Basis Tracking Scheme in Satellite Quantum Key Distribution

Morio Toyoshima, Hideki Takenaka, Yozo Shoji, Yoshihisa Takayama, Masahiro Takeoka, Mikio Fujiwara, Masahide Sasaki

Published Jan 1, 2011• 25 citations

Abstract

Satellite quantum key distribution is a promising technique that overcomes the limited transmission distance in optical-fiber-based systems. The polarization tracking technique is one of the key techniques in the satellite quantum key distribution. With free-space quantum key distribution between an optical ground station and a satellite, the photon polarization state will be changed according to the satellite movement. To enable polarization based quantum key distribution between mobile terminals, we developed a polarization-basis tracking scheme allowing a common frame of reference to be shared. It is possible to orient two platforms along a common axis by detecting the reference optical signal only on the receiver side with no prior information about the transmitter's orientation. We developed a prototype system for free-space quantum key distribution with the polarization-basis tracking scheme. Polarization tracking performance was 0.092° by conducting quantum key distribution experiments over a 1 km free space between two buildings in a Tokyo suburb.

DOI: 10.1155/2011/254154

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