Single-photon Sagnac interferometer

Abstract

We present the first experimental demonstration of the optical Sagnac effect\nat the single-photon level. Using a high quality guided-wave heralded single-\nphoton source at 1550 nm and a fibre optics setup, we obtain an interference\npattern with net visibilities up to (99.2 $\\pm$ 0.4%). On the basis of this\nhigh visibility and the compactness of the setup, the interest of such a system\nfor fibre optics gyroscope is discussed.\n