| Autor: |
Mancini, Andrea, Giliberti, Valeria, Alabastri, Alessandro, Calandrini, Eugenio, De Angelis, Francesco, Garoli, Denis, Ortolani, Michele |
| Rok vydání: |
2018 |
| Předmět: |
|
| Druh dokumentu: |
Working Paper |
| Popis: |
We investigate local heat generation by molecules at the apex of polymer-embedded vertical antennas excited at resonant mid-infrared wavelengths, exploiting the surface enhanced infrared absorption (SEIRA) effect. The embedding of vertical nanoantennas in a non-absorbing polymer creates thermal isolation between the apical hotspot, the locus of heat generation, and the heat sink represented by the substrate. Vibrational mid-infrared absorption by strongly absorbing molecules located at the antenna apex then generates nanoscale temperature gradients at the surface. We imaged the thermal gradients by using a nano-photothermal expansion microscope, and we found values up to 10 K/microm in conditions where the radiation wavelength resonates with both the molecule vibrations and the plasmonic mode of the antennas. Values up to 1000 K/microm can be foreseen at maximum quantum cascade laser power. The presented system provides a promising thermoplasmonic platform for antenna-assisted thermophoresis and resonant mid-infrared photocatalysis. |
| Databáze: |
arXiv |
| Externí odkaz: |
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