title: Etchant-based design of gold tip apexes for plasmon-enhanced Raman spectromicroscopy.
abstract: In this paper, we gain insight into the design and optimization of plasmonic (metallic) tips prepared with dc-pulsed voltage electrochemical etching gold wires, provided that, a duty cycle is self-tuned. Physically, it means that etching electrolyte attacks the gold wire equally for all pulse lengths, regardless of its surface shape. Etchant effect on the reproducibility of a curvature radius of the tip apex is demonstrated. It means that the gold conical tips can be designed chemically with a choice of proper etchant electrolyte. It is suggested to use a microtomed binary polymer blend consisting of polyamide and low density polyethylene, as a calibration grating, for optimizing and standardizing tip-enhanced Raman scattering performance.
authors: Department of Optics and Nanophotonics, Institute of Physics, Kazan Federal University, Kremlevskaya, 16, Kazan 420008, Russia; Tatarstan Academy of Sciences, Baumana str., 20, Kazan 420111, Russia. Electronic address: skharint@gmail.com.
authors: Sergey
authors: S
authors: Kharintsev
authors: National Laboratory Astana, Nazarbayev University, Kabanbay batyr ave., 53, Astana 01000, Kazakhstan; STC NMST, Moscow Institute for Electronic Technology, Moscow, Russia.
authors: Alexander
authors: A
authors: Alekseev
authors: DSM Resolve, 6167 RD Geleen, The Netherlands.
authors: Joachim
authors: J
authors: Loos
keywords: Calibration grating; Electrochemical etching; Enhanced optical spectroscopy; Etchant effect; Gold tip; Optical antenna; Optical near-field; Polyethelene; Polyimide; Surface plasmon; Tip-enhanced Raman scattering