title: Enhancing single-nanoparticle surface-chemistry by plasmonic overheating in an optical trap.
abstract: Surface-chemistry of individual, optically trapped plasmonic nanoparticles is modified and accelerated by plasmonic overheating. Depending on the optical trapping power, gold nanorods can exhibit red shifts of their plasmon resonance (i.e., increasing aspect ratio) under oxidative conditions. In contrast, in bulk exclusively blue shifts (decreasing aspect ratios) are observed. Supported by calculations, we explain this finding by local temperatures in the trap exceeding the boiling point of the solvent that cannot be achieved in bulk.
authors.affiliation: Photonics and Optoelectronics Group, Department of Physics and Center for Nanoscience, Ludwig-Maximilians-Universität München, Amalienstr. 54, 80799 Munich, Germany.
authors.forename: Weihai
authors.initials: W
authors.lastname: Ni
authors.affiliation: Photonics and Optoelectronics Group, Department of Physics and Center for Nanoscience, Ludwig-Maximilians-Universität München, Amalienstr. 54, 80799 Munich, Germany.
authors.forename: Haojin
authors.initials: H
authors.lastname: Ba
authors.affiliation: Photonics and Optoelectronics Group, Department of Physics and Center for Nanoscience, Ludwig-Maximilians-Universität München, Amalienstr. 54, 80799 Munich, Germany.
authors.forename: Andrey A
authors.initials: AA
authors.lastname: Lutich
authors.affiliation: Photonics and Optoelectronics Group, Department of Physics and Center for Nanoscience, Ludwig-Maximilians-Universität München, Amalienstr. 54, 80799 Munich, Germany.
authors.forename: Frank
authors.initials: F
authors.lastname: Jäckel
authors.affiliation: Photonics and Optoelectronics Group, Department of Physics and Center for Nanoscience, Ludwig-Maximilians-Universität München, Amalienstr. 54, 80799 Munich, Germany.
authors.forename: Jochen
authors.initials: J
authors.lastname: Feldmann
mesh_terms: D003460:Crystallization / Q000379:methods*; D006046:Gold / Q000737:chemistry*; D006361:Heating / Q000379:methods*; D046911:Macromolecular Substances / Q000737:chemistry; D008422:Materials Testing; D053768:Metal Nanoparticles / Q000737:chemistry* / Q000648:ultrastructure*; D008968:Molecular Conformation; D052898:Optical Tweezers; D010316:Particle Size; D020349:Surface Plasmon Resonance / Q000379:methods*; D013499:Surface Properties
chemical_list: D046911:Macromolecular Substances; D006046:Gold