Am Montag, den 23. Juni 2025, um 12:00 Uhr c.t., hält Prof. Dr. Jean-Pierre van Helden im Rahmen unseres Physikalischen Kolloquiums seinen Antrittsvortrag.
Van Helden ist Professor für Experimentalphysik – Spektroskopie von Atomen und Molekülen mit Lasermethoden an der Fakultät für Physik und Astronomie und spezialisiert sich auf die Entwicklung von Methoden für die Plasmadiagnostik. Sein Vortrag trägt den Titel „Shining Light on Reactive Plasmas“.
Low-temperature non-equilibrium reactive molecular plasmas play a crucial role in numerous industrial processes, most noteworthy in the microelectronics industry, and hold significant potential for driving important chemical transformations. Despite an ever-growing number of applications, the common processes occurring in low and atmospheric pressure plasmas and their post-discharge regions are poorly understood. In particular, the non-thermal plasma chemical kinetics, and especially the molecular origins of many chemical and transport processes near and at surfaces and, even in biological cells in the case of plasma biotechnology. A detailed understanding of the complex physicochemical processes requires precise information on the atomic and molecular composition of the plasma, on the absolute concentrations and temperatures of the reactive species in the plasma, their population distribution among the quantum states and their reaction kinetics.
This requires novel non-intrusive and in-situ diagnostic tools that go beyond the state of the art available today. In this presentation, I will introduce highly sensitive laser-based diagnostics we are developing and applying using novel lasers in the mid- and far-infrared, including cavity-enhanced spectroscopy, frequency comb spectroscopy, and THz spectroscopy, to characterize plasmas and their interactions with surfaces. In particular, frequency comb-based spectroscopy techniques offer a unique combination of broad bandwidth and high spectral resolution, enabling the simultaneous detection of multiple species in plasmas.
Abstract des Vortrags von Prof. van Helden.
Prof. Dr. Hendrik Hildebrandt will give an introduction to the lecture.
The faculty cordially invites all interested parties. The event will take place in lecture hall HNB.
All dates of the Physics Colloquium can be found here.
Foto: Prof. Jean-Pierre van Helden © RUB, Marquard