Fig. 1. (a) Localized surface plasmon oscillation; (b) spreading surface plasmon

Fig. 2. Fitted curves of dielectric constant of nanoparticles in Palik experiment. (a) Au nanoparticles; (b) Ag nanoparticles

Fig. 3. Optical field distributions of (a) sphere, (b) cubic, (c) cylindrical and (d) pyramid prism-shaped Au nanoparticles

Fig. 4. Purcell factors of single nanoparticles with different shapes. (a) Single Au nanoparticle; (b) single Ag nanoparticle

Fig. 5. Simulation model of single and bimetallic nanoparticles

Fig. 6. Resonance electric field distributions of metal nanoparticle. (a) Single Au nanoparticle; (b) double Au nanoparticles

Fig. 7. Purcell factors corresponding to single and double metal nanoparticles with different length of long axis. (a) Single Au nanoparticle; (b) single Ag nanoparticle; (c) double Au nanoparticles; (d) double Ag nanoparticles

Fig. 8. Purcell factors corresponding to single and double metal nanoparticles with different length of short axis. (a) Single Au nanoparticle; (b) single Ag nanoparticle; (c) double Au nanoparticles; (d) double Ag nanoparticles

Fig. 9. Purcell factors corresponding to single and double metal nanoparticles at different refractive indices of environmental material. (a) Single Au nanoparticle; (b) single Ag nanoparticle; (c) double Au nanoparticles; (d) double Ag nanoparticles

Fig. 10. Purcell factors corresponding to single and double metal nanoparticles at different distances. (a) Single Au nanoparticle; (b) single Ag nanoparticle; (c) double Au nanoparticles; (d) double Ag nanoparticles

Fig. 11. Simulation model of bimetallic nanometer ellipsoid shell

Fig. 12. Effect of filling material of bimetallic nanometer ellipsoidal shell on Purcell factor. (a) Double Au nanometer ellipsoid shell; (b) double Ag nanometer ellipsoid shell

Fig. 13. Effect of ellipsoidal shell thickness on Purcell factor of double metal nanometer ellipsoidal shell. (a) Double Au nanometer ellipsoid shell; (b) double Ag nanometer ellipsoid shell