Plasma-induced surface cooling

• Published in: Nature communications Vol. 13; no. 1; p. 2623
• Main Authors: Tomko, John A., Johnson, Michael J., Boris, David R., Petrova, Tzvetelina B., Walton, Scott G., Hopkins, Patrick E.
• Format: Journal Article
• Language: English
• Published: London Nature Publishing Group UK 12.05.2022; Nature Publishing Group; Nature Portfolio
• Subjects: 639/301/299; 639/301/930/12; 639/766/1960; 639/766/25; Adsorbates; Charged particles; Cooling; Cooling effects; Energy; Fluctuations; Humanities and Social Sciences; Materials engineering; multidisciplinary; Photons; Plasma; Plasma cooling; Plasma diagnostics; Plasma interactions; Plasmas (physics); Science; Science (multidisciplinary); Surface cooling; Temperature effects; Thermal response
• ISSN: 2041-1723; 2041-1723
• DOI: 10.1038/s41467-022-30170-5

Plasmas are an indispensable materials engineering tool due to their unique ability to deliver a flux of species and energy to a surface. This energy flux serves to heat the surface out of thermal equilibrium with bulk material, thus enabling local physicochemical processes that can be harnessed for material manipulation. However, to-date, there have been no reports on the direct measurement of the localized, transient thermal response of a material surface exposed to a plasma. Here, we use time-resolved optical thermometry in-situ to show that the energy flux from a pulsed plasma serves to both heat and transiently cool the material surface. To identify potential mechanisms for this ‘plasma cooling,’ we employ time-resolved plasma diagnostics to correlate the photon and charged particle flux with the thermal response of the material. The results indicate photon-stimulated desorption of adsorbates from the surface is the most likely mechanism responsible for this plasma cooling. When a plasma interacts with a surface, different thermal effects may arise. Here, the authors explore plasma interactions with a surface that produce a surface cooling effect.