Title: Robust, high brightness, degenerate entangled photon source at room temperature,
Abstract: We report on a compact, simple and robust high brightness entangled photon
source at room temperature. Based on a 30 mm long periodically poled potassium
titanyl phosphate (PPKTP), the source produces non-collinear, type0 phase
matched, degenerate photons at 810 nm with pair production rate as high 39.13
MHz per mW at room temperature. To the best of our knowledge, this is the
highest photon pair rate generated using bulk crystals pump with
continuous-wave laser. Combined with the inherently stable polarization Sagnac
interferometer, the source produces entangled state violating the Bells
inequality by nearly 10 standard deviations and a Bell state fidelity of 0.96.
The compact footprint, simple and robust experimental design and room
temperature operation, make our source ideal for various quantum communication
experiments including long distance free space and satellite communications.