Bright and highly-polarized single-photon sources in visible based on droplet-epitaxial GaAs quantum dots in photonic crystal cavities

Solid-state single-photon sources with high purity, high brightness and a large degree of linear polarization are appealing to photonic quantum technologies. However, high-performance single-photon sources based on InAs/GaAs quantum dots (QDs) so far are operating at near infrared range, which limits the detection efficiency and potential compatibility with atomic quantum memory in visible. Here, we explore GaAs droplet epitaxial QDs emitting in visible to achieve bright, pure and highly-polarized single-photon emission via coupling to photonic crystal cavities.