title: On-Fly Femtosecond-Laser Fabrication of Self-Organized Plasmonic Nanotextures for Chemo- and Biosensing Applications.
abstract: Surface-enhanced Raman scattering (SERS) and surface-enhanced photoluminescence (SEPL) are emerging as versatile widespread methods for biological, chemical, and physical characterization in close proximity of nanostructured surfaces of plasmonic materials. Meanwhile, single-step, facile, cheap, and green technologies for large-scale fabrication of efficient SERS or SEPL substrates, routinely demonstrating both broad plasmonic response and high enhancement characteristics, are still missing. In this research, single-pulse spallative micron-size craters in a thick Ag film with their internal nanotexture in the form of nanosized tips are for the first time shown to demonstrate strong polarization-dependent enhancement of SEPL and SERS responses from a nanometer-thick covering Rhodamine 6G layer with average enhancement factors of 40 and 2 × 10(6), respectively. Additionally, the first detailed experimental study is reported for physical processes, underlying the formation mechanisms of ablative nanotextures on such "thick" metal films. Such mechanisms demonstrate a complex "hybrid" fluence-dependent ablation character-appearance of spallative craters, typical for bulk material, at low fluences and formation of upright standing nanotips (frozen nanojets), usually associated with thin-film ablation, in the crater centers at higher fluences. Moreover, special emphasis was made on the possibility to reshape the nanotopography of such spallative craters through multipulse laser-induced merging of their small nanotips into larger ones. The presented approach holds promise to be one of the cheapest and easiest-to-implement ways to mass-fabricate various efficient spallation-nanotextured single-element plasmonic substrates for routine chemo- and biosensing, using MHz-repetition-rate femtosecond fiber laser sources with multiplexed laser-beams.
authors.affiliation: School of Natural Sciences, Far Eastern Federal University (FEFU) , 8 Sukhanova str., Vladivostok 690041, Russia.|Institute of Automation and Control Processes (IACP), Far Eastern Branch of Russian Academy of Science (FEB RAS) , 5 Radio Str., Vladivostok 690041, Russia.
authors.forename: Aleksandr
authors.initials: A
authors.lastname: Kuchmizhak
authors.affiliation: School of Natural Sciences, Far Eastern Federal University (FEFU) , 8 Sukhanova str., Vladivostok 690041, Russia.
authors.forename: Evgenii
authors.initials: E
authors.lastname: Pustovalov
authors.affiliation: School of Natural Sciences, Far Eastern Federal University (FEFU) , 8 Sukhanova str., Vladivostok 690041, Russia.|Institute of Automation and Control Processes (IACP), Far Eastern Branch of Russian Academy of Science (FEB RAS) , 5 Radio Str., Vladivostok 690041, Russia.
authors.forename: Sergey
authors.initials: S
authors.lastname: Syubaev
authors.affiliation: School of Natural Sciences, Far Eastern Federal University (FEFU) , 8 Sukhanova str., Vladivostok 690041, Russia.|Institute of Automation and Control Processes (IACP), Far Eastern Branch of Russian Academy of Science (FEB RAS) , 5 Radio Str., Vladivostok 690041, Russia.
authors.forename: Oleg
authors.initials: O
authors.lastname: Vitrik
authors.affiliation: Institute of Automation and Control Processes (IACP), Far Eastern Branch of Russian Academy of Science (FEB RAS) , 5 Radio Str., Vladivostok 690041, Russia.
authors.forename: Yuri
authors.initials: Y
authors.lastname: Kulchin
authors.affiliation: Institute of Automation and Control Processes (IACP), Far Eastern Branch of Russian Academy of Science (FEB RAS) , 5 Radio Str., Vladivostok 690041, Russia.|Samara National Research University , 34 Moskovskoe Shosse, Samara 443086 Russia.
authors.forename: Aleksey
authors.initials: A
authors.lastname: Porfirev
authors.affiliation: Samara National Research University , 34 Moskovskoe Shosse, Samara 443086 Russia.
authors.forename: Svetlana
authors.initials: S
authors.lastname: Khonina
authors.affiliation: Institute of Automation and Control Processes (IACP), Far Eastern Branch of Russian Academy of Science (FEB RAS) , 5 Radio Str., Vladivostok 690041, Russia.|ITMO University , Kronverkskiy Prospect 49, St. Petersburg 197101, Russia.|Lebedev Physical Institute , Leninskiy Prospect 53, Moscow 119991, Russia.
authors.forename: Sergey
authors.initials: S
authors.lastname: Kudryashov
authors.affiliation: Institute of Automation and Control Processes (IACP), Far Eastern Branch of Russian Academy of Science (FEB RAS) , 5 Radio Str., Vladivostok 690041, Russia.|Lebedev Physical Institute , Leninskiy Prospect 53, Moscow 119991, Russia.
authors.forename: Pavel
authors.initials: P
authors.lastname: Danilov
authors.affiliation: Lebedev Physical Institute , Leninskiy Prospect 53, Moscow 119991, Russia.
authors.forename: Andrey
authors.initials: A
authors.lastname: Ionin
mesh_terms: D015374:Biosensing Techniques; D007834:Lasers; D008670:Metals; D049329:Nanostructures; D013059:Spectrum Analysis, Raman; D013499:Surface Properties
chemical_list: D008670:Metals
keywords: femtosecond pulses; nanotopography reshaping; red−green−blue color analysis; spallative crater; surface-enhanced Raman scattering; surface-enhanced photoluminescence