Photoluminescence of Femtosecond Laser-irradiated Silicon Carbide

Abstract: Silicon carbide (SiC) is the leading wide-bandgap semiconductor material, providing mature doping and device fabrication. Additionally, SiC hosts a multitude of optically active point defects (color centers), it is an excellent material for optical resonators due to its high refractive index and an outstanding material for mechanical resonators due to its high Q/f product. Moreover, epitaxial graphene layers can be grown as ultrathin electrodes and provide the potential to fine-tune color center resonances. These characteristics render SiC an ideal platform for experiments with single color centers towards quantum technologies including coupling color centers towards cooperative effects. A crucial step towards harnessing the full potential of the SiC platform includes technologies to create color centers with defined localization and density, e.g.\ to facilitate their coupling to nano-photonic structures and to observe cooperative effects. Here, silicon vacancy centers (V$_{Si}$) stand out as no impurity atom is needed and high-thermal budget annealing steps can be avoided. We characterize the effect of localized, femtosecond laser irradiation of SiC, investigating surface modifications and photoluminescence including Raman spectroscopy and optical lifetime measurements.