講演情報
[16a-P01-12]Optical binding dynamics of gold nanoparticles with linearly patterned gold nanodisks
〇(M2)Mu-En Li1, Chih-Hao Huang1, Xu Shi3, Kosei Ueno3, Boris Louis4, Roger Bresoli-Obach5, Johan Hofkens4, Hiroaki Misawa1,2,3, Hiroshi Masuhara1 (1.Nat'l Yang Ming Chiao Tung Univ., Taiwan, 2.Okayama Univ., Japan, 3.Hokkaido Univ., Japan, 4.KU Leuven, Belgium, 5.Universitat Ramon Llull, Spain)
キーワード：
optical binding、gold nanoparticles、optical matter
Optical trapping of colloidal nanoparticles is considered a promising approach for constructing active optical matter. Our group has reported a dynamic matter based on the optical binding between non-irradiatedand irradiated gold (Au) nanoparticles (NPs) by tightly focusing a linearly polarized 1064 nm laser at glass/solution interface. In 2024 JSAP meeting, we discussed the polarization-dependent optical trapping dynamics of Au NPs in the presence of the lithographically fabricated Au nanodisk (ND) pattern, where several specific trapping positions are observed with a displacement to the center of the beam when the laser is shifted along the alignment of the Au ND pattern.In this report, we extend the investigation of the far-field interaction between patterned Au NDs and free NPs. Without introducing the Au ND pattern, the geometry of one to seven optically trapped Au NPs located inside the focus, and the dynamics of the eighth and ninth Au NPs fluctuate outside the irradiation area are analyzed. In contrast, characteristic trapping behaviors are observed by shifting the trap 400 nm perpendicularly to the alignment of the Au ND pattern. The least stable triangular configuration of six particles is stably formed. Upon shifting the laser, the pentagonal configuration, which is commonly observed configuration in the absence of Au ND pattern, is recovered accompanied by the slightly suppressed rotational motion, suggesting the weakened far-field interaction between the Au NDs and NPs. These results open a new approach to prepare active optical matter based on the interaction between reconfigurable colloidal particles and designed lithographical pattern.