Comparison of surface plasmon polariton characteristics of Ag- and Au-based InGaN/GaN nanocolumn plasmonic crystals

We characterized surface plasmon polariton (SPP) coupling in InGaN/GaN nanocolumn (NC) arrays with Ag- and Au-based plasmonic crystals (PlCs). In both the Ag- and Au-based NC-PlCs, the standing wave SPPs enhanced the light emission from the InGaN/GaN NC arrays. The finite-difference time-domain calculations reproduced the general tendency of the experimental results for the photoluminescence enhancement ratio and SPP resonant wavelength. For the Ag-based NC-PlCs, a stronger electric field intensity was obtained, and the SPP resonance could be controlled over a wide range of wavelengths. Therefore, significant emission enhancement in the visible light region can be realized for the Ag-based NC-PlCs.