Emerging materials for plasmonics
Résumé
Over the past two decades, noble metal nanoparticles have attracted an increasing interest because of their varied and complex optical properties. These properties are mainly governed by the collective oscillations of conduction electrons called "plasmons". In particular, the excitation of the latter by optical fields leads to a local exaltation of the electromagnetic field on the surface of the nanoparticle. This very intense nanosource makes it possible to envisage nanometric optical concepts by controlling, manipulating and amplifying light at this scale. Very recently, new metals have been proposed as suitable plasmonic materials to tackle emerging applications of plasmonics, e.g. high-temperature applications, nanochemistry, sensing, or active plasmonics where gold and silver do not possess all the required properties, such as high-temperature sustainability, or catalytic activity. For these reasons, gold and silver are currently reducing their predominance in plasmonics to the benefit of other metals, metal oxides and alloys that constitute a new emerging branch of research. Following this burgeoning variety of plasmonic materials, it becomes useful to conduct a comprehensive and comparative study in order to clearly establish the relative efficiencies of these new plasmonic materials. In this context, I will discuss on the emerging materials and try to present the advantages of different materials like aluminum, nickel, nitrides or bimetallic.