Figure 3
From: Plasmon enhanced optical tweezers with gold-coated black silicon
Wavelength–dependent characterization of trapping efficiency.
Trapping efficiency, Q, as a function of the trapping laser wavelength, measured at distances (a) z = 1 μm, (b) z = 4 μm, (c) z = 6 μm, (d) z = 8 μm and (e) z = 10 μm above the nanostructured silicon substrate, coated with Cu/Au. Solid lines: Gaussian fit to the data. Trapping data were obtained with the femtosecond laser setup. The y-error corresponds to the standard deviation of the trapping efficiency measurement. (f) Maximum trapping efficiency, Qmax, resulting from the fits presented in Fig. 3a–e, as a function of the relative distance, z, between the trapping laser beam focus and the substrate. Relative distance is the measured distance with respect to the zero position. Solid line: exponential fit to the data. The y-error corresponds to the error of the Gaussian fit.
