Diffraction of collinear correlated photon pairs by an ultrasonic wave

Abstract

The phenomenon of collinear correlated photon pairs diffraction by an ultrasonic wave is investigated for Bragg incidence. A BBO crystal was used for producing collinear correlated photon pairs via type-I spontaneous parametric down-conversion (SPDC I-type). It is shown experimentally that the Bragg angle for photon pairs diffraction is identical to the one corresponding to single photons diffraction. The numbers of single photons and photon pairs counts in discrete diffraction orders were measured as functions of the Raman-Nath parameter. Similarly, the number of coincidence photon counts in separate diffraction orders was also investigated. What is more, simple analytical formulas are derived which perfectly describe experimentally obtained data. OCIS codes: (050.1940) Diffraction; (230.1040) Acousto-optical devices; (230.4110) Modulators; (270.4180) Multiphoton processes.