Simultaneous enhancement of light extraction and spontaneous emission using a partially reflecting metasurface cavity

The enhancement of light extraction efficiency (LEE), spontaneous emission rate (SER), and far-field directivity is of crucial importance in single-photon sources. For this reason, we propose here a partially reflecting metasurface cavity (PRMC) concept that simultaneously enhances these three parameters in a planar cavity configuration. The LEE is enhanced by enforcing the emitted light to radiate perpendicularly to the device so as to suppress wave trapping loss, the SER is enhanced by properly confining the field near the source, and the far-field directivity is enhanced by maximizing the radiation aperture of the device. The PRMC structure is designed using a recent surface susceptibility metasurface synthesis technique and demonstrated by full-wave simulation to provide LEE and SER enhancements by factors of 4.0 and 1.9, respectively, and a half-power beam width of 22.5.. Therefore, this PRMC structure has a promising potential for single-photon source with higher efficiency and single-photon purity.