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arXiv · 1805.07067

Photothermal Engineering of Graphene Plasmons

Renwen Yu·Qiushi Guo·Fengnian Xia·F. Javier García de Abajo
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Abstract

Nanoscale photothermal sources find important applications in theranostics, imaging, and catalysis. In this context, graphene offers a unique suite of optical, electrical, and thermal properties, which we exploit to show self-consistent active photothermal modulation of its nanoscale response. In particular, we predict the existence of plasmons confined to the optical landscape tailored by continuous-wave external-light pumping of homogeneous graphene. This result relies on the high electron temperatures achievable in optically pumped clean graphene while its lattice remains near ambient temperature. Our study opens a new avenue toward the active optical control of the nanophotonic response in graphene with potential application in photothermal devices.

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Renwen Yu, Qiushi Guo, Fengnian Xia, F. Javier García de Abajo. 2018-05-18. Photothermal Engineering of Graphene Plasmons. https://doi.org/10.1103/physrevlett.121.057404

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