Selective Purcell enhancement of two closely linked zero-phonon transitions of a silicon carbide color center
Significance Semiconductor point defects have shown great promise in their application to quantum information and sensing in the solid state. However, it is an ongoing challenge to efficiently access the light emitted by these spin-active defects and, furthermore, to enhance the emission at wavelengths that can be used to create indistinguishable photons. Such emission enhancement can be achieved by placing the defects within optical microcavities. Here, using 1D photonic crystal cavities, we report the significant enhancement of point-defect emission in silicon carbide, which hosts a suite of intriguing spin-active defects. In addition to measuring large enhancements, we also demonstrate how the cavity coupling can potentially allow access to a variety of information about the defects and their environment. Point defects in silicon carbide are rapidly becoming a platform of great interest for single-photon generation, quantum sensing, and quantum information science. Photonic crystal cavities (PCCs) can serve as an efficient light–matter interface both to augment the defect emission and to aid in studying the defects’ properties. In this work, we fabricate 1D nanobeam PCCs in 4H-silicon carbide with embedded silicon vacancy centers. These cavities are used to achieve Purcell enhancement of two closely spaced defect zero-phonon lines (ZPL). Enhancements of >80-fold are measured using multiple techniques. Additionally, the nature of the cavity coupling to the different ZPLs is examined.