(a) Experimentally measured trap stiffness for the upright BNA orientation and the inverted BNA orientation,and FDTD calculations of the intensity enhancement and absorption cross-section for the upright BNA orientation and the inverted orientation.^[75] (b) Surface plot of the trapping efficiency, Q, as a function of the relative distance, z, between the trapping laser beam focus and the Cu/Au-coated nanostructured silicon substrate and as a function of the trapping wavelength, obtained with the femtosecond laser setup.^[76] (c) Au NPs trapped by the Ti-sapphire laser in the CW mode (left) and femtosecond-pulse mode (right), Withe arrows show the directions of polarization.^[42] (d) Nonlinear trapping of Au NPs under various polarization conditions.^[43] (e) DNA assembly on a thin Au film with no nanostructure using femtosecond NIR laser irradiation.^[77] (left) Fluorescence spectra obtained before (black), upon (red), and after (gray) femtosecond laser irradiation. (right) Temporal profiles of the fluorescence intensity as the laser was switched on and off repetitively (red, repetition time ≈ 60 s) and without femtosecond laser irradiation (black).