Development of silicon carbide photonics for quantum technologies

Quantum information sciences offer novel capabilities in the fields of computation, data security and sensing. In order to deliver these improvements, information needs to be encoded in a physical quantum system the realization of which is technologically challenging. Even though several platforms have been proposed for computation, quantum information encoded in nonclassical states of light is going to play a central role since the classical fiber technology already provides an almost ideal transmitting medium. Furthermore, a hybrid approach formed together with solid state emitters could meet the non-trivial requirement needed for quantum computation. In the past ten years, efforts have been placed in integrating the bulky optical components required to manipulate nonclassical states of light, giving birth to the field of quantum photonics. Between all the different materials proposed, 3C silicon carbide (SiC) meets all the complex requirements needed for photonic quantum technologies and the development of essential components to this scope is the main subject of this thesis. The design, fabrication and characterization of small modal area waveguides, grating couplers and ring resonators made in SiC are reported. Four wave mixing was demonstrated thanks to the small modal volume achieved in the ring resonator and the Kerr coefficient of SiC was retrieved. The realization of photonic crystal cavities is also investigated with the aim to harness quantum emitters. Thanks to the demonstration of coupling between confined and propagating surface waves, SiC is a potential platform for quantum applications in the mid-infrared. Finally, the generation of photon pairs in the near-infrared by means of third order nonlinear process is reported using ring resonators fabricated in silicon nitride