Open AccessSingle-photon interference and router-control in an optic fiber Sagnac interferometer
Author(s) -
Wu Guang,
Changyu Zhou,
Huidan Zeng
Publication year - 2004
Publication title -
wuli xuebao
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 0.199
H-Index - 47
ISSN - 1000-3290
DOI - 10.7498/aps.53.698
Subject(s) - physics , optics , interferometry , fibre optic gyroscope , single mode optical fiber , photon , sagnac effect , interference (communication) , optical path , optical fiber , telecommunications , computer science , channel (broadcasting)
A novel scheme to realize stable single-photon interference and router-control is demonstrated in this paper. Phase difference between clockwise and counter-clockwise single-photons is controlled by time-division phase modulation in an optic fiber Sagnac loop. Due to the annular geometric configuration of the Sagnac loop, clockwise and counter-clockwise single-photons travel the same optical path and have the same slowly-varying phase drifts, which are automatically compensated. Furthermore, clockwise and counter-clockwise single-photons encounter the same polarization mode dispersion, which is also automatically compensated at the exit port of the Sagnac interferometer. Long-distance single-mode optic fiber at 1550 nm is used in our experimental realization. Fringe visibility of single-photon interference higher than 98% and fidelity of single-photon router-control higher than 90% have been obtained in a Sagnac fiber loop of 5 km. We also realized a stable single-photon interference in Sagnac fiber loops as long as 27 and 52 km. The corresponding fringe visibilities were higher than 94% and 84%, respectively.