Robust plasmonicFano resonance in π-shaped nanostructure

Supporting Information

Zhendong Yan,1 Ping Gu,1Wenjing Bao,2 Wei Du,1Zhuo Chen,1,*Xinhua Xia,2 and Zhenlin Wang1,*

1School of Physics and National Laboratory of Solid State Microstructures

2School of Chemistry and Chemical Engineering, Nanjing University, Nanjing 210093, China

*Corresponding authors: (Z.C.)

(Z.L.W.)

Contents

Fig. S1The magnetic diople modes of L-shape and the two π-shaped nanostructures

Fig. S2The magnified SEM image of Au PODT array andthe calculation of scattering, absorption and extinction of an individual PODT

Fig.S3Experimental and calculated transmittance spectra of a single triangle array upon exposure to the dielectric media with different index of refraction

Fig. S1The magnetic diople modes of L-shape and the two π-shaped nanostructures

Fig. S1The magnetic diople modes of L-shape and the two π-shaped nanostructures under normal incident excitation with the polarization state shown the top-left. The schematic of the three types of nanoparticles and the corresponding magnetic field (H), surface current distributions and vertical component (Hz) of magnetic field are shown in left, middle and right columns. The corresponding geometrical parameters are given asthe same as shown in Fig. 1and Fig. 3 in the main text

Fig. S2 The magnified SEM image of Au PODT array and the calculation of scattering, absorption and extinction of an individual PODT

Fig. S2:aThe magnified SEM image of Au PODT array. The distance (d) between bases of the PODTnanostructuresis around 80 nm, which means the plasmonic coupling between the PODTnanostructure bases is very weak.bThe calculated spectra of scattering, absorption and extinction for an individual Au PODTunder normally incident light with y polarization.The arrows labeled as p3 and p4correspond to the twoplasmonic modes of the corresponding PODT array.cThe simulatedabsorption spectrum ofan individual Au PODT and the transmittance spectrum ofthe corresponding PODT arraywith y polarization. The results plotted in cshow that both a single PODT and the PODT array havealmost identical plasmon modes under the y-polarization excitation, which means that the influence of the plasmonic coupling between the PODTnanostructure bases isvery weak and could be neglected

Fig.S3Experimentaland calculated transmittance spectra of a single triangle (ST) array upon exposure to dielectric matrix with different values of refractive index (n)

Fig. S3:aExperimentaland b calculated transmittance spectra for the Au ST sampleexposed to dielectric matrix with different refractive index under a normal incidenceofy-polarized light. c Linear plot of the localized surface plasmon resonance (LSPR)wavelength shifts of the Auπ-shape sample as shown in Fig.3b in the main text and Au ST vs refractive index of the embedding medium. The obtained FoM is 3.5 for Au π-shaped sample and 0.9 for ST