Title :
Free space quantum key distribution with coherent polarization states
Author :
Heim, B. ; Elser, Dominique ; Bartley, Tim ; Wittmann, Christoffer ; Sych, Denis ; Leuchs, Gerd
Author_Institution :
Inst. of Opt., Inf. & Photonics, Univ. of Erlangen-Nuremberg, Nuremberg, Germany
Abstract :
Free space QKD over an atmospheric channel was demonstrated in 1996 for the first time. Since then, several prepare-and-measure and entanglement-based schemes have been implemented (for a detailed overview, see). All of these systems use single-photon detectors, and therefore have to employ spatial, spectral and/or temporal filtering in order to reduce background light. In our system, we use an alternative approach: with the help of a bright local oscillator (LO), we perform homodyne measurements on weak coherent polarization states.
Keywords :
homodyne detection; light coherence; light polarisation; optical communication equipment; optical filters; optical links; photodetectors; quantum cryptography; quantum entanglement; quantum optics; spatial filters; bright local oscillator; coherent polarization states; entanglement; free space quantum key; homodyne measurements; single-photon detectors; spatial filtering; spectral filtering; temporal filtering; Atmospheric measurements; Laser beams; Local oscillators; Optical filters; Optical noise; Optical polarization; Optical propagation; Performance evaluation; Timing jitter; Wavelength measurement;
Conference_Titel :
Lasers and Electro-Optics 2009 and the European Quantum Electronics Conference. CLEO Europe - EQEC 2009. European Conference on
Conference_Location :
Munich
Print_ISBN :
978-1-4244-4079-5
Electronic_ISBN :
978-1-4244-4080-1
DOI :
10.1109/CLEOE-EQEC.2009.5196232
