Single-beam inscription of plasmon-induced surface gratings

Abstract

The formation of gratings on gold nanoprisms arrays by plasmon-mediated reduction of a diazonium salt is investigated. Nanosphere lithography (NSL) is used to produce large surfaces of gold nanoprisms that are effective at reducing diazonium salts by producing hot electrons through excitation of localized surface plasmon resonances (LSPRs). Using single beam irradiation, we report here on the formation of periodic structures formed from the diazonium salts and that follow the NSL structures. On plasmonically active nanoprism substrates, the electric field enhancement promotes chemical reduction and hence modifies the grafting direction and grating properties of the ripples. The nanoprisms act as a plasmon guide which widens the pitch of the self-organized gratings and can even alter it from straight lines into a crisscross pattern. • Single beam irradiation of diazonium salt forms surface relief grating. • Light-induced reduction of diazonium salts solution yields polyaryl thin films. • Combination with plasmonic substrate enable to control the growth direction and shape of the diffractive elements. • Plasmon-mediated self-developing surface gratings enables creation of a variety of surface structures.