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Light induced selective heating of nanostructured pyrolitic graphite surfaces investigated by Raman scattering

Abstract:

Nanostructured surfaces of highly oriented pyrolytic graphite (HOPG) were characterized by Raman spectroscopy. The disc-shape nanostructures ∼110 nm high and with two different diameters ∼147 and 217 nm are prepared on HOPG using hole-mask colloidal lithography and oxygen reactive ion etching. Significant roughening of the HOPG surface is introduced by the nano-fabrication process, but the nano-disc structures preserves their crystalline structure. Resonant light absorption results in selective heating of nanostructures, although the surrounding medium remains relatively unaffected. Temperature differences of up to 350 K were measured under irradiation with ∼11 mW/μm2. Further increase of the light intensity leads to combustion of structures. © 2013 Elsevier B.V. All rights reserved.