The field of silicon photonics has grown tremendously over the past 2 decades. Mature platforms are now available from several major fabs around the world.  Silicon photonics is commercially used in datacom and telecom applications and widely investigated for applications in sensing, computing and quantum optics. However, some important building blocks are still missing or difficult to realize. This includes lasers and amplifiers but also linear optical switches and modulators, non-linear elements and single photon sources and detectors.  In this project I will investigate how these can be realized by the integration of materials such as III-V semiconductors, quantum dots and ferro-electrics on the silicon platform.  The work will investigate both the integration methods as such as the realization of functional building blocks.