Cavity-enhanced second-harmonic generation of narrowband 655 nm lightSkok, Krištof (Avtor) Kaltenbaek, Rainer (Mentor) optično frekvenčno podvajanjeoptični resonatortehnika Pound-Drever-Hallpasovna širinafinesaIn the Laboratory for Quantum Optics and Quantum Foundations at the Faculty for Mathematics and Physics, University of Ljubljana, a new type of source of narrowband entangled photons is being build. Entangled photons will be generated via spontaneous parametric downconversion (SPDC), pumped by 655 nm light, which is produced from 1310 nm laser light via a non-linear optical phenomenon, second-harmonic generation (SHG). The process occurs in a non-linear crystal positioned in an actively stabilized optical cavity. The cavity is a resonator for laser light and enhances the light intensity inside, and consequently increasing the SHG conversion efficiency. The narrow cavity bandwidth leads to a narrow linewidth of 655 nm light, which is an essential design goal of the entire experiment. The thesis provides a theoretical treatment of second-harmonic generation, of optical cavities and of Pound-Drever-Hall technique, which is used for the active stabilization of the cavity. The experimental part describes the optical and electrical layout of the experimental setup and examines measurement results that characterize the bandwidth and quality of the optical cavity.20222022-09-24 08:15:02Magistrsko delo/naloga141188sl