Fast quantitative optical detection of heat dissipation by surface plasmon polaritons

Abstract

Heat management at the nanoscale is an issue of increasing importance. In optoelectronic devices the transport and decay of plasmons contribute to the dissipation of heat. By comparison of experimental data and simulations we demonstrate that it is possible to gain quantitative information about excitation, propagation and decay of surface plasmon polaritons (SPPs) in a thin gold stripe supported by a silicon membrane. The temperature-dependent optical transmissivity of the membrane is used to determine the temperature distribution around the metal stripe with high spatial and temporal resolution. This method is complementary to techniques where the propagation of SPPs is monitored optically, and provides additional information which is not readily accessible by other means. In particular, we demonstrate that the thermal conductivity of the membrane can also be derived from our analysis. The results presented here show the high potential of this tool for heat management studies in nanoscale devices.

Remote Excitation of Hot Electrons via Propagating Surface Plasmons

“…It can be challenging, particularly in resonant structures, to disentangle the consequences of plasmonic hot carrier generation (from, e.g., the decay of localized surface plasmons or propagating surface plasmon polaritons (SPPs)) from competing effects, such as lattice and electron heating or the creation of electron–hole excitations due to direct absorption . Prior experiments on atomic-scale junctions have shown evidence of plasmon-assisted transport, with possible roles of hot carriers. − Time-resolved pump–probe measurements have provided significant insight of the relaxation and thermalization of electrons and the heat dissipation of SPPs in plasmonic nanostructures. ,− Electron emission in the pulsed regime must additionally distinguish between conventional photoemission and strong plasmon-based fields. − However, many applications of interest for hot carrier generation likely require continuous illumination, such as photocatalysis and solar energy conversion.…”