ISSN Online: 2377-424X
ISBN Print: 978-1-56700-474-8
ISBN Online: 978-1-56700-473-1
International Heat Transfer Conference 16
LASER-ASSISTED TIP-SUBSTRATE CONFIGURATION FOR EXPLORING BALLISTIC THERMAL TRANSPORT
Résumé
The focusing of electromagnetic radiation induced by metallic tips is of great interest in applications of material characterization, surface science, and manufacturing. In this work, the photo-thermal conversion in silicon assisted by the focusing of optical field confined between an Au nanotip and the substrate is studied through numerical simulations. The near-field optical enhancement at different incident frequencies and angles of illumination is calculated. Field enhancement up to 64 within sub-10 nm region is found around the tip apex under 532 nm p-polarized incidence. As the Au tip approaches a silicon substrate, the optical field in the gap region is significantly enhanced, leading to amplified absorption in the silicon substrate. At the contacting tip-substrate configuration, a nanoscale heat source is generated by the conversion from the induced optical enhancement. The heat source has strong power density (~3 × 1015 W/m3 under an incident laser of 2 × 107 W/m2) within sub-10 nm region, which is feasible for the study of ballistic thermal transport.