Bio-inspired plasmonic leaf for enhanced light-matter interactions

The mathematical concept of fractals is widely applied to photonics as planar structures ranging from terahertz resonators, optical antennas, to photodetectors. Here, instead of a direct mathematical abstract, we design a plasmonic leaf with fractal geometry from the outline of a leaf from Wargrave...

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Bibliographic Details
Main Authors: Liu Changxu, Mao Peng, Guo Qinghua, Han Min, Zhang Shuang
Format: Article
Language:English
Published: De Gruyter 2019-06-01
Series:Nanophotonics
Subjects:
Online Access:https://doi.org/10.1515/nanoph-2019-0104
Description
Summary:The mathematical concept of fractals is widely applied to photonics as planar structures ranging from terahertz resonators, optical antennas, to photodetectors. Here, instead of a direct mathematical abstract, we design a plasmonic leaf with fractal geometry from the outline of a leaf from Wargrave Pink. The enhanced light-matter interactions are observed numerically from the improvement in both absorption and near-field intensification. To demonstrate the effect experimentally, a three-dimensional fractal structure is realised through direct laser writing, which significantly improves the photothermal conversion. By virtue of the self-similarity in geometry, the artificial leaf improves the absorption of a 10-nm-thick gold film with 14 ×  temperature increment compared to flat Au film. Not limited to the proof-of-concept photothermal experiment demonstrated here, the fractal structure with improved light-matter interactions can be utilised in a variety of applications ranging from non-linear harmonic generation, plasmonic-enhanced fluorescence, to hot electron generation for photocatalysis.
ISSN:2192-8606
2192-8614