Effects of plasmon mode on crystallization behaviors by plasmonic trapping

We design and fabricate triangular trimer gold nanostructures with two different edge lengths and investigate effects of plasmon modes on the crystallization behaviors induced by plasmonic optical trapping. The location of the enhanced electric field depends on the edge lengths (170 and 230 nm) of the triangular trimer. The crystallization of NaClO3 was induced by the 1064-nm laser irradiation on a single trimer structure. The generated crystal is attributed to be a metastable crystal with birefringence. Polymorphic transformation occurs in the case of continuous laser irradiation onto a 230 nm trimer, but intriguingly never in the case of a 170 nm trimer. These results will contribute to the understanding of the crystallization mechanism of NaClO3 by plasmonic trapping and give a novel insight to polymorphic transformation.