Project R-15940

Fabrication of Optically Active Group-IV Defects in Diamond for Single Photon Emission and Photonic Integration (Research)

The primary aim of this study is to develop stable, bright optically active defects, also known as color centers, based on Group IV elements in diamond that are capable of single photon emission. In To this end, Group IV elements such as germanium and tin have been employed to create these defects using the microwave plasma-enhanced chemical vapor deposition (MW PE CVD) technique, were successfully fabricated at Hasselt University. However, a significant challenge remains: the high refractive index of diamond limits photon extraction efficiency, resulting in only faint emission from the color centers. To address this issue, the integration of color centers into photonic structures—particularly diamond pillars—is proposed as a promising approach to enhance photon collection. While current expertise does not yet include diamond structuring for photonic applications, a research stay at the University of Kassel is planned to gain hands-on experience in electron beam lithography and diamond etching. This acquired knowledge will be used to optimize photonic structures upon return to Hasselt University, with the aim of significantly improving the optical performance of color centers. The research stay is expected to provide a solid foundation for future advancements in quantum photonics using engineered diamond defects.

08 September 2025 - 17 September 2025