Table 1.

Characteristic dimensions of the isolated resonators as measured by AFM: A-SRR (outer diameter), Cr-SRR (outer diameter), C-SRR (outer diameter) and U-SRR (lateral dimension), respectively. Plasmon resonant wavelength as measured by FTIR corresponding to square array composed of resonators of the same size and with pitches of approximately twice the characteristic dimensions. The isolated resonators (p = 10 µm) were too sparse to yield a measurable far-field FTIR spectrum for a direct comparison. The uncertainties in the resonators dimensions represent a single standard deviation in the measurements on nominally identical resonators. The uncertainty in the plasmon resonant wavelengths and Q factors represent a single standard deviation from Lorentian fitting of FTIR resonance peak.

Shape	Characteristic dimension (µm)	Resonance Wavelength (µm)	Q-factor
A-SRR	1.75 ± 0.05	8.85 ± 0.05	13.9 ± 0.5
Cr-SRR	1.65 ± 0.05	9.05 ± 0.05	5.1 ± 0.3
C-SRR	1.20 ± 0.05	9.00 ± 0.05	5.7 ± 0.3
U-SRR	1.15 ± 0.05	9.70 ± 0.05	3.6 ± 0.3