All-Optical Control of a Single Plasmonic Nanoantenna–ITO Hybrid

• Published in: Nano letters 2011-06, Vol.11 (6), p.2457-2463
• Main Authors: Abb, Martina, Albella, Pablo, Aizpurua, Javier, Muskens, Otto L
• Format: Article
• Language: English
• Subjects: Applied sciences; Collective excitations (including excitons, polarons, plasmons and other charge-density excitations); Condensed matter: electronic structure, electrical, magnetic, and optical properties; Condensed matter: structure, mechanical and thermal properties; Electronic structure and electrical properties of surfaces, interfaces, thin films and low-dimensional structures; Electronics; Exact sciences and technology; Gold - chemistry; Low-dimensional structures (superlattices, quantum well structures, multilayers): structure, and nonelectronic properties; Metal Nanoparticles - chemistry; Molecular electronics, nanoelectronics; Particle Size; Physics; Semiconductor electronics. Microelectronics. Optoelectronics. Solid state devices; Silicon Dioxide - chemistry; Surface and interface electron states; Surface Properties; Surfaces and interfaces; thin films and whiskers (structure and nonelectronic properties); Tin Compounds - chemistry
• ISSN: 1530-6984; 1530-6992
• DOI: 10.1021/nl200901w

We demonstrate experimentally picosecond all-optical control of a single plasmonic nanoantenna embedded in indium tin oxide (ITO). We identify a picosecond response of the antenna–ITO hybrid system, which is distinctly different from transient bleaching observed for gold antennas on a nonconducting SiO2 substrate. Our experimental results can be explained by the large free-carrier nonlinearity of ITO, which is enhanced by plasmon-induced hot-electron injection from the gold nanoantenna into the conductive oxide. The combination of tunable antenna–ITO hybrids with nanoscale plasmonic energy transfer mechanisms, as demonstrated here, opens a path for new ultrafast devices to produce nanoplasmonic switching and control.