Selective Generation of V2 Silicon-Vacancy Color Centers in Silicon Carbide

Silicon-vacancy color centers in the 4H polytype of silicon carbide (4H-SiC) are a promising candidate for photonic quantum information processing with outstanding spin-optical properties. Compared with the V1 type, V2 silicon-vacancy color centers in 4H-SiC can exhibit longer spin coherence time at room temperature and better compatibility with nanophotonic structures. However, silicon-vacancy color centers in 4H-SiC are typically formed in the V1 type with a significantly higher probability than the V2 type. Here, we demonstrate the selective generation of V2 silicon-vacancy color centers in 4H-SiC. This is realized by the mask-less focused ion beam implantation of lithium ions on the m-plane of 4H-SiC. The ratio between the numbers of V2 and V1 silicon-vacancy color centers increases exponentially with decreasing implantation doses. Nearly 70% of implantation locations with color centers only show V2 centers at low doses. Our results represent a critical step towards the scalable implementation of quantum information processing based on SiC photonics and provide further insights into the mechanism of color center formation.