Gap Nanoantennas toward Molecular Plasmonic Devices
Figure 9
Femtosecond pulsed excitation over gold dimers. The excitation wavelength is fixed at 565 nm, and its power density is varied from 0.9 (a) to 6.3 kW/cm2 (i). The dedicated sample here is a 100 × 100 m array of dimers with a 100 nm diameter, a 30 nm gap, and a 60 nm thickness, that matches the excitation wavelength. A 50 nm layer of perylene in PMMA is spin-coated over the gold dimers as in Figure 4(a). The graph displays the individual response of selected dimers (circled on the image series) as a function of the excitation power. From one dimer to another, one can see various power dependences of the signal, going from close to linear behavior (for D1) to overquadratic one (in D3 and D4).
