Calculated plasmonic enhancement of spontaneous emission from silicon nanocrystals with metallic gratings

The spontaneous emission rate (SER) enhancement due to the surface plasmon polariton (SPP) band gap effect of metallic gratings was evaluated by calculating the dispersion relation and electromagnetic field distribution simultaneously. Within the luminescence range of silicon nanocrystals (Si-NC) (ℏω = 1.9 eV–1.6 eV), the calculated peak Purcell factors for Au-, Ag-, and Al-Si3N4 gratings are 266.9–30.1, 80.2–22.6, and 78.7–20.3, respectively. These results indicate that the common metals such as Au, Ag and Al, whose SPP resonance frequencies/energies are rather higher, can be adopted to enhance the SER of Si-NCs with the help of metallic gratings.