This project takes a new approach for realizing the dream of microcavity light sources emitting in the ultraviolet-blue-green wavelength regime, enabling innovative solutions e.g. in biomedicine. In spite of an impressive materials-oriented research effort in gallium nitrides, no ultraviolet-blue-green microcavity light sources have been demonstrated with acceptable performance: the output power is too low, they are very energy-inefficient, and the lifetime is only a few minutes, at most. This is in sharp contrast to cutting-edge microcavity lasers and LEDs emitting at near-infrared wavelengths. Therefore, this project takes a device-oriented approach, profiting from our leading research on near-infrared sources, while solidly supported by materials experts. I am forming a group that will consider all critical problems, mainly to achieve (1) good optical feedback, (2) efficient current injection, and (3) precise tuning of the optical gain, the feedback mirrors and the cavity to the same wavelength. Although the materials research has resulted in basic epitaxial structures of high quality, our unique device perspective is crucial; for instance problem (1) is addressed by novel high-contrast structures, and for (2) and (3) we will develop current aperture and hybrid techniques inspired by those used in infrared devices. For expertise on materials physics and fundamental optical functions in GaN-based materials, I will collaborate closely with EPFL, Lausanne.
Docent vid Chalmers, Microtechnology and Nanoscience (MC2), Photonics
Funding years 2014–2019