Formation of ordered and disordered dielectric/metal nanowire arrays and their plasmonic behavior

摘要

We have recently shown that dielectric/metal composite nanowires can exhibit very strong surface enhanced Raman (SERS) signals, when arranged in a random 3D geometry. Since we believe that the intersections of nanowires are critical in generating the high electric fields necessary for this enhancement, we are investigating this effect under more controlled conditions. Thus, we will discuss the formation of nanowire arrays by in-situ growth, achieved by the control of nanowire material/substrate combination, as well as ex-situ nanowire array formation involving e-beam lithography. The effects of nanowire geometry and the resulting SERS behavior show the importance of the dielectric/metal configuration, as well as the importance of nanowire geometry in the SERS effect.