In recent years, quantum optics has revolutionized the way we think about computing and communication. The experimental demonstration of quantum teleportation, quantum key distribution for secure communication and many other exciting achievements in the field of quantum computing will enable novel applications that were considered to be impossible only a few decades ago.
At the heart of all these systems are single photon sources: laser-like systems that emit a single photon at a time, unlocking the quantum nature of light. Traditionally, these sources are realized using exotic materials with a large second order nonlinearity and table-top pump lasers resulting in expensive and bulky single-photon emitters. Quantum optical circuits have recently been able to benefit from scaling trends enabled by the tremendous advances made in silicon photonics. At the moment, however, the quest for good integratable sources on these platforms is still open. Ideally, highly nonlinear materials should be used. Current materials used on the silicon platform such as silicon and silicon nitride do not possess such a strong second order nonlinearity because they are centro-symmetric.
Imec, however, has recently demonstrated the wafer-scale epitaxial growth of laser-grade III-V materials directly on silicon. Unlike silicon, III-V materials do not possess an inverse symmetric crystalline structure, making them excellent candidates for single photon emission enabled by nonlinear optics. The III-V nano-ridges grown on a silicon substrate can be coupled to a silicon photonic circuit which will enable the integration of an efficient single photon source directly with the quantum optical system on a single chip the size of a fingernail. Such a tight integration scheme paves the way for the wide-spread deployment of quantum optic systems.For this reason, we are looking for a PhD candidate to pioneer the development of such next-generation integrated quantum sources. The student will perform an in-depth study of the involved physical processes to gain insight into the possibilities and limitations of such a system. This activity encompasses a literature review, numerical modelling but also the experimental characterization of some of the building blocks in the system. In a later stage the student will use the knowledge assembled in the first phase to demonstrate an integrated single photon emitter.
Required background: MSc Electrical engineering, Photonic engineering, Physics
Type of work: 40% modeling/simulation, 40% processing/experimental, 10% literature, 10% reporting
Supervisor: Roel Baets, Bart Kuyken
Daily advisor: Yannick De Koninck
The reference code for this position is 1812-25. Mention this reference code on your application form.