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arXiv · 2310.06774

Optical assembly of nanostructures mediated by surface roughness

Robert G. Felsted·Jaehun Chun·Gregory K. Schenter·Alexander B. Bard·Xiaojing Xia·Peter J. Pauzauskie
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Abstract

Rigorous understanding of the self-assembly of colloidal nanocrystals is crucial to the development of tailored nanostructured materials. Despite extensive studies, a mechanistic understanding of self-assembly under non-equilibrium driven by an external field remains an ongoing challenge. We demonstrate self-assembly by optical tweezers imposing an external attractive field for cubic-phase sodium yttrium fluoride nanocrystals. We show that surface roughness of the nanocrystals is a decisive factor for contact leading to assembly between the nanocrystals, manifested by the roughness-dependent hydrodynamic resistivity. This provides direct evidence that dynamics are equally important to energetics in understanding self-assembly. These results have implications in a wide variety of different fields, such as in understanding the factors that mediate oriented attachment-based crystal growth or in interpreting the structure of binding sites on viruses.

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Robert G. Felsted, Jaehun Chun, Gregory K. Schenter, Alexander B. Bard, Xiaojing Xia, Peter J. Pauzauskie. 2023-10-10. Optical assembly of nanostructures mediated by surface roughness. https://doi.org/10.1103/physrevlett.134.088201

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