SINGLE PHOTONS GENERATOR

PROBLEM TO BE SOLVED: To provide a high efficient single photons generator which takes out photons emitted from quantum dot as a single photons pulse possible to be actually utilized. SOLUTION: A quantum dot 1 is embedded into an optical waveguide 2 consisting of optical waveguides 2A and 2B. In the optical waveguide 2; a single photon 8 is penetrated and connected with an optical waveguide 4 through dichroic filter 3 reflecting an excitation pulse light 7, the excitation pulse light 7 is penetrated and connected with an optical waveguide 6 through a dichroic filter 5 reflecting the single photons 8, the single photon 8 is emitted from the quantum dot 1 excited by absorbing the excitation pulse 7, and this single photon 8 is taken out through the optical waveguides 2 and 4. The quantum dot 1 is a microcrystal of direct gap semiconductor, and not larger than four times of exciton Bohr radius aB*. Its profile is an ellipsoid-like shape with 1 principal axis longer than the other principal axis, cylindrical shape or the like, and photons of plane polarization polarized in a major axis direction 9 is taken out from the quantum dot 1. COPYRIGHT: (C)2007,JPO&INPIT