Optical printing of gold nanoparticles: an interplay between nanoscale optical and thermal forces

GARGIULO, JULIAN; IANINA L. VIOLI; ZAZA, CECILIA; BRICK, THOMAS; CORTES, EMILIANO; MAIER, STEFAN A.; FERNANDO STEFANI

Porquerolles Island

Workshop; 1st Summer School Photothermal Effects in Plasmonics; 2018

CNRS

Among the various methods fordecorating surfaces with colloidalnanoparticles (NPs), OpticalPrinting stands out because itenables the fabrication of patternsof arbitrary design on planesubstrates (Figure) with no needof any previous steps of physicalor chemical patterning [1]. Using optical forces, AuNPs can be manipulated and positioned with anaccuracy higher than 50 nm.However, it was not possible to print identicalNPs closer to each other than 300 nm [2]. Lightabsorption by printed NPs and subsequent localheating produces photothermal forces that are asstrong as the optical forces and disturb the printingprocess. Here, we model and quantify thesephotothermal effects considering thermophoreticand thermos-osmotic forces. By optimizing heatdissipation, we demonstrate for the first time opticalprinting of connected NPs (Fig.2) [3].