Électrons lumineux. – (Klavs Hansen / LPT / Seminar). – 28/05/2024, 14H

Klavs Hansen (Université de Tianjin, république populaire de Chine)

Seminar LPT, 28/05/2024, 14H, 3R1, seminar room, 3rd floor

Abstract :
The emission of thermal electromagnetic radiation from hot molecules and clusters has long been assumed to be a simple matter of vibrational transitions. However, it is becoming increasingly clear that also electrons can be excited thermally and emit photons. The rates for these emissions can reach microsecond timescales for metal clusters, more than three orders of magnitude shorter than vibrational IR radiation. Besides often occurring on very short time scales, the rates also are very molecule-specific ; Every electron counts. In the talk I will present the special features that allow experimental determination of the phenomenon, and give a tour of some results obtained for molecules and clusters.

[1] Piero Ferrari, Ewald Janssens, Peter Lievens, Klavs Hansen, Radiative cooling of size-selected gas phase clusters, Int. Rev. Phys. Chem. 38 (2019) 405-440

[2] C. Walther, G. Dietrich, W. Dostal, K. Hansen, S. Krückeberg, K. Lützenkirchen and L. Schweikhard, Radiative Cooling of a Small Metal Cluster : The Case of V^+_13, Phys. Rev. Lett. 83 (1999) 3816

[3] Shimpei Iida, Wei Hu, Rui Zhang, Piero Ferrari, Kei Masuhara, Hajime Tanuma, Haruo Shiromaru, Toshiyuki Azuma, and Klavs Hansen, Thermal radiative cooling of carbon cluster cations C^+_N , N = 9, 11, 12, 17 − 27, Mon. Not. R. Astron. Soc. 514 (2022) 844–851