Tunable diode laser based biphoton source for quantum spectroscopy

Photon pairs generated by spontaneous parametric down-conversion (SPDC) are essential for a number of quantum-optics experiments. By utilizing periodically poled (PP) waveguide structures high flux rates of biphotons in one transversal mode can be obtained. The biphoton source presented here is explicitly designed for quantum spectroscopic application and is based on a frequency doubled broad area external cavity diode laser (BA-ECDL) that pumps SPDC inside a PPLN waveguide crystal. A time correlated single photon counting device has been used for the correlation measurements.