title: Plasmon-assisted delivery of single nano-objects in an optical hot spot.
abstract: Fully exploiting the capability of nano-optics to enhance light-matter interaction on the nanoscale is conditioned by bringing the nano-object to interrogate within the minuscule volume where the field is concentrated. There currently exists several approaches to control the immobilization of nano-objects but they all involve a cumbersome delivery step and require prior knowledge of the "hot spot" location. Herein, we present a novel technique in which the enhanced local field in the hot spot is the driving mechanism that triggers the binding of proteins via three-photon absorption. This way, we demonstrate exclusive immobilization of nanoscale amounts of bovine serum albumin molecules into the nanometer-sized gap of plasmonic dimers. The immobilized proteins can then act as a scaffold to subsequently attach an additional nanoscale object such as a molecule or a nanocrystal. This universal technique is envisioned to benefit a wide range of nano-optical functionalities including biosensing, enhanced spectroscopy like surface-enhanced Raman spectroscopy or surface-enhanced infrared absorption spectroscopy, as well as quantum optics.
authors.affiliation: ICFO - Institut de Ciencies Fotoniques , Mediterranean Technology Park, 08860 Castelldefels (Barcelona), Spain.
authors.forename: Christopher M
authors.initials: CM
authors.lastname: Galloway
authors.forename: Mark P
authors.initials: MP
authors.lastname: Kreuzer
authors.forename: Srdjan S
authors.initials: SS
authors.lastname: Aćimović
authors.forename: Giorgio
authors.initials: G
authors.lastname: Volpe
authors.forename: Manuel
authors.initials: M
authors.lastname: Correia
authors.forename: Steffen B
authors.initials: SB
authors.lastname: Petersen
authors.forename: Maria Teresa
authors.initials: MT
authors.lastname: Neves-Petersen
authors.forename: Romain
authors.initials: R
authors.lastname: Quidant