Fig. 1: The schematics and illustrations of the DBR (distributed Bragg reflector)-CBG structure.

a Schematic diagram of the DBR-CBG structure. b Numerical simulation of the far-field distribution of the electrical intensity of emission. The blue arrow denotes the dipole orientation. c Simulations with and without the DBR-CBG, demonstrating an 8.81-fold improvement in collection efficiency. d Top view of a scanning electron microscope (SEM) image of a single DBR-CBG structure