Figure 3
From: Optical tweezing and binding at high irradiation powers on black-Si
Fluorescence micrographs of 1-dimmensionally (1D) trapping behavior of polystyrene beads (d = 500 nm) on a MFBS substrate (light intensity I = 640 kW/cm2). Laser irradiation area (focus diameter, 1.1 μm) in the figures is smaller than that in Figs 1 and 2 (3 μm). 0 s (c) means the starting time of the laser irradiation. Irradiation time is given in the figure. After the first trapping event of a single particle (a–c), second particle was trapped on the top of the firstly-trapped particle (d–f). Schematic illustration shows this “snowman structure formation” by optical binding. Further continuing irradiation, the third particle was trapped on the top of the secondary-trapped particle (g–i). Schematic illustration next to (i) shows the 1D-trapping behavior. The image (d) in Fig. 2 also corresponds to the 1D-trapping.
