High-output power GaN-LED based on surface plasmon enhancement

In recent years, metallic nano-light-emitting diode (LED) arrays have gained wide attention as new-generation lighting materials. This study evaluates the optical properties of triangular array Ag nanodisc GaN-LED and analyses its effects on internal radiation and external light extraction of LED by changing the cycle and height of the Ag nanodisc. We use FDTD software for simulation. The results showed that the increase in the spontaneous emission rate depended on the localised surface plasmon (LSP) generated by the Ag nanodisc and the multiple quantum well layer, considering the coupling between the surface plasmon and the dipole enhanced the internal energy. Owing to the optimal structural parameters, the spontaneous emission rate was enhanced by 4.79 times, and the power integral of the internal radiation source increased from 0.037 to 0.177. Furthermore, the enhanced energy from coupling did not radiate outward and was limited to the surface of the Ag nanodisc. Additionally, a two-dimensional photonic crystal structure was embedded in the p-layer to transform the LSP into a radiation plasmon. When the transmittance was 0.32, the top surface power integral increased from 0.021 to 0.131, light output power increased by 5.47 times, and the factor of light extraction efficiency increased by 1.79 times. These results provide practical values that can be applied in optimising the design of high-performance GaN-based LED.