Presentation Information
[8a-P01-4]Dynamic Optical Binding of Gold Nanoparticles on Fabricated Gold Nanodisk Array with Single- and Double-Wavelength Periodicity
〇(M2)Tien Hsi Tsai1, Mu-En Li1, Xu Shi2, Kosei Ueno2, Boris Louis4, Roger Bresoli-Obach5, Hiroaki Misawa1,2,3, Johan Hofkens4, Hiroshi Masuhara1 (1.National Yang Ming Chiao Tung Univ., Taiwan, 2.Hokkaido Univ., Japan, 3.Okayama Univ., Japan, 4.KU Leuven, Belgium, 5.Universitat Ramon Llull, Spain)
Keywords:
optical trapping,gold nanoparticles,gold nanodisk
Optical manipulation is a unique technique that enables the trapping of micro- and nanoparticles at the focal point of a tightly focused laser beam. Our group demonstrated the trapping of 200 nm gold nanoparticles (Au NPs) at the glass/solution interface, forming a single dumbbell-shaped assembly with linearly aligned and fluctuating Au NPs within and outside the focus, respectively. To control this swarming morphology, we employed microchannels, dual beams, and a lithographically fabricated Au nanodisk (ND) array with single-wavelength periodicity to mimic particle arrangements at the focus. The morphology was switched from bi- to uni-directional assemblies by shifting the laser focus on the array.
In this study, we expect that an Au ND array with double-wavelength periodicity generates an unconventional behavior of swarming. Figure 1 illustrates how swarm morphology varies with the laser focus position. By shifting the irradiation focus along the array, distinct assembly patterns emerge. Focusing the laser at the midpoint between two adjacent NDs (Figure 1a) results in a symmetric distribution, whereas focusing directly on a single ND (Figure 1b) produces a bi-directional, asymmetric assembly. Notably, center arrangement and swarming assembly on both sides of the ND array are different from those ND array with single-wavelength periodicity. These results will be detailed and discussed in this presentation.
In this study, we expect that an Au ND array with double-wavelength periodicity generates an unconventional behavior of swarming. Figure 1 illustrates how swarm morphology varies with the laser focus position. By shifting the irradiation focus along the array, distinct assembly patterns emerge. Focusing the laser at the midpoint between two adjacent NDs (Figure 1a) results in a symmetric distribution, whereas focusing directly on a single ND (Figure 1b) produces a bi-directional, asymmetric assembly. Notably, center arrangement and swarming assembly on both sides of the ND array are different from those ND array with single-wavelength periodicity. These results will be detailed and discussed in this presentation.