Formation of plasmonic nanoparticle arrays –rules and recipes for an ordered growth (Phys. Status Solidi B 2/2016)

Ordered arrays of metallic nanoparticles offer promise of new devices employing localised plasmon resonances. Common self‐organising synthesis methods of metallic nanoparticles typically lack long‐range order, while production of well‐ordered lithographically patterned samples is difficult and time consuming. In their Feature Article on pp. 198–205 , Fleischer et al. present recent results on self‐organised deposition on stepped oxide templates leading to the formation of highly ordered linear nanoparticle arrays. Their formation has been monitored in‐situ by reflectance anisotropy spectroscopy (RAS), a spectroscopic optical technique allowing for the measurement of the plasmon resonance frequency already during formation. RAS has been employed to understand the growth of nanoparticles in terms of ad‐atom diffusion on various oxide surfaces, growth temperatures and metal species, giving insights on the conditions required to achieve well‐ordered nanoparticle arrays. The cover illustration sketches the RAS setup and shows in‐situ spectra of regular Ag nanoparticle arrays on a stepped Al2O3 surface. The SEM image in the background is representative of the order achieved in the self‐assembled nanoparticle arrays.