Diamond photo-electric detectors with introducing silicon-vacancy color centers

Abstract

Color centers in diamond is a type of promising candidate for the application of quantum sensing under photo-luminescent or photo-electric mode. Photoinduced charge carrier separation for nitrogen-vacancy (NV) centers makes diamond an excellent visible photodetector. To date, the introduction of silicon-vacancy (SiV) color centers on the photo-electrical and photo-luminescent properties of diamond remains unclear. To address this issue, high-quality silicon-doped single crystal diamond (Si-SCD) photodetectors were prepared by microwave plasma chemical vapor deposition (MPCVD). It is found that an extremely low dark current of several pA can be achieved with an oxygen-terminated surface. In addition, although the introduction of SiV centers enhances the device's absorption of near-ultraviolet/visible (NUV/Vis) illumination, it has little impact on the solar blind detection performance, exhibiting a responsivity of 36.2 mA/W and detectivity of 2.10×1012 Jones. Meanwhile, the Si-doped detector also exhibits 102 to 103 times higher responses to NUV/Vis signals and a faster cut-off speed. Moreover, a SiV PL enhancement of 50% was achieved at external electrical bias, which shows a higher electric pumping efficiency compared with polycrystalline diamond devices.