En col·laboració amb la Universitat Autònoma de Barcelona (UAB) i la Universitat de Barcelona (UB)

In this master's thesis we study two filtering techniques, first the Faraday anomalous dispersion optical filter (FADOF) and second a monolithic Fabry-Pérot interferometer with the aim of filtering down-converted photon pairs resonant with the D1 line of 87Rb. The geometrical properties of a plano-convex lens with a high- refectivity dielectric coating applied on both sides provides us with a long term stability and a tunable Fabry-Pérot cavity suitable for narrowband frequency filtering. A transmission of 30% is reached, a free spectral range of 19.2 GHz and a bandwidth of 47.5 MHz are measured providing a proof-of-concept for a future implementation. In addition, a 852 nm DFB laser is mounted and tested by performing saturated absorption spectroscopy with the aim of locking the laser. However, the results show that the laser was mode hopping.