Vorträge im WS 2017/2018

  • 24.10.2017

    Dr. Gerard van Rooij (Dutch Institute for Fundamental Energy Research DIFFER, Eindhoven) abstract
    Electrification of chemical industry: a key role for plasma chemistry

    Sustainable energy generation by means of wind or from solar radiation through photovoltaics or concentrated solar power will continue to increase its share of the energy mix. Intermittency due to e.g. day/night cycle, regional variation in availability, and penetration of sustainable energy into sectors other than electricity such as the chemical industry necessitates means of storage, transport and energy conversion on a large scale. A promising option is the synthesis of chemicals and artificial fuels using sustainable energy. A truly circular economy requires that the raw materials are the thermodynamically most stable ones such as CO_2 and N_2 . In this contribution it will be highlighted how plasma chemistry can potentially combine compatibility with e.g. intermittency and localized production to activate these molecules with maximum energy efficiency, essentially due to preferential vibrational excitation (causing inherently strong out-of-equilibrium processing conditions that achieve selectivity in the reaction processes). Examples will be discussed of research carried out at DIFFER to ultimately enable a scale up to chemical industrial applications.


  • 07.11.2017

    Dr. Volker Schulz-von der Gathen (Fakultät für Pysik und Astronomie der Ruhr-Universität Bochum)
    Microplasma arrays: Concept, configuration, characteristics and potential applications


Der Vortrag von Dr. Schulz-von der Gathen am 07. November fällt auf Grund von Krankheit leider aus! Der Neue Termin wurde für die 09.01.2018 festgelegt.
  • 21.11.2017

    Dr. Michael Klick (Plasmatrex, Berlin) abstract
    Zur Plasma-Wand-Wechselwirkung in industriellen HF-Plasmen​

    Die Plasma-Wand-Wechselwirkung ist für die industrielle Nutzung von chemisch aktiven HF-Plasmen von fundamentaler Bedeutung. Im Bereich des Plasma-Ätzens in der Halbleiter-Industrie ist die sogenannte Konditionierung von Prozesskammern nach einer Reinigung im Abstand von einigen Wochen oder Monaten Vorbedingung für die Freigabe zur Fertigung. Dies trifft aber auch für PECVD-Kammern im laufen-den Betrieb zu, da die auch auf der Wand abgeschiedene Schicht i.a. wieder zurück geätzt werden muss. [mehr im abstract]

  • 28.11.2017

    Prof. Dr. Claus Lämmerzahl (ZARM, Bremen) abstract
    An operational foundation of General Relativity and the search for Quantum Gravity

    General Relativity seems to be incompatible with the principles of quan-tum theory. Therefore, a new theory - Quantum Gravity - is expected to replace General Relativity which also should lead to new physical effects. However, no finally worked out Quantum Gravity theory exists. In order to be able to already design experiments searching for expected effects of Quantum Gravity one has to carry out such experiments which give a foundation of General Relativity. Such a program is described in this talk: Based on an constructive axiomatic approach to General Relativity from Ehlers, Pirani, and Schild experiments are described which have the poten-tial to find deviations from standard physics related to Quantum Gravity.

  • 12.12.2017

    Prof. Dr. Peter Schmelcher (Universität Hamburg) abstract
    Mesoscopic Physics with Ultracold Atoms: From Few- to Many-Body Systems

    Bose-Einstein condensates, matter waves and generally ultracold atomic physics have seen over the past two decades a breathtaking development and represent nowadays an important part of modern quantum physics. We provide here an overview of me-soscopic aspects of ultracold atomic structures and processes in tightly confining traps. For strongly interacting ultracold atoms novel tunneling mechanisms occur which play a key role for the atomic transport and the formation of rich quantum pha-ses. We demonstrate a variety of tunneling processes which are the basis of the emerging field of atomtronics, some of them being counterintuitive, such as the tun-neling of repulsively bound atomic clusters.
    A special focus will be on the none-quilibrium quantum dynamics of ultracold bosonic and fermionic ensembles where correlations determine the response due to a quantum quench or a continuous driving. Recent methodological developments allow to explore the correlated dynamics in the crossover regime from few- to many-body systems in order to understand the emergence of collective behaviour.

  • 19.12.2017

    Dr. Kählert (Reserviert)

  • 09.01.2018

    Dr. Volker Schulz-von der Gathen (Fakultät für Pysik und Astronomie der Ruhr-Universität Bochum) abstract
    Microplasma arrays: Concept, configuration, characteristics and potential applications

    Microplasma arrays belong to the class of low temperature non-equilibrium atmospheric pressure plasma devices. They consist of huge numbers of about 100 micrometer size cavities regularly positioned on a common ground. These structures are usually generally manufactured applying microstructure techniques on silica wafers [1], but other configurations have been investigated recently. Being basically dielectric barrier discharges, the devices are typically driven by a single power supply at kHz frequencies at voltages of a few hundred volts. Due to the small dimensions strong fields exist in close contact with the surfaces that introduces new physical features. The geometric configuration results e.g. in unique features of discharge dynamics as ionization waves. A huge number of possible applications have been proposed over the last years [2]. The examples range from photonic applications as light generation and detection to large scale surface treatments or use as meta materials. In this talk we will give a basic description of the concepts of microplasma arrays, their operation and some application possibilities. Subsequently we will describe some of the physical features observed mainly by analysis of optical emission.

    [1] J.G. Eden, S.-J. Park, and K.-S. Kim, „Arrays of non-equilibrium plasmas confined to microcavities: an emerging frontier in plasma science and its applications“ Plasma Sources Science and Technology, 2006, 15, S67-S73
    [2] J.G. Eden, and S.-J. Park, „Microcavity plasma devices and arrays: a new realm of plasma physics and photonic applications“, Plasma Phys Control Fusion, 2005, 47, B83-B92

  • 16.01.2018

    Prof. Dr. Ulrich Stroth (TU München/IPP) abstract
    Über die zentrale Bedeutung des Plasmarandes für die Fusionsforschung

    Der Votrag beschreibt die physikalischen Prozesse, die den Rand des Fusionsplasmas auszeichnen, wo der Übergang vin einem bis zu 100 Millionen Grad heißen Plasma zu den umgebenden matiellen Wänden vollzogen wird. Die Forschung auf diesem Gebiet ist stark interdisziplinär. Sie greift auf Konzepte aus verschiedenen Fachgebieten zurück, angefangen bei der Festkörperphysik, über die Atmo- und Molekülphysik und die Magnetohydrodynamik, bis hin zur Plasmaturbulenz. Durch die Darstellung ausgewählter Prozesse wird das Zusammenwirken der verschiedenen Einflüsse auf das Plasma sichtbar gemacht.
    Das Verständnis des Plasmaranders ist insbesondere dazu notwendig, um eine sichere Leistungabfuhr aus Fusionsplasmen zu gewährleisten. Mögliche Realisierungendes Plasmarandes für ein Fusionskraftwerk werden beispielhaft and den Experimenten des MPI für Plasmaphysik, dem Tokamak ASDEX Upgrade und dem Stellarator Wendelstein 7-X, dargestellt.

  • 23.01.2018

    Prof. Dr. Stefan Kuhr (University of Strathclyde, Glasgow) abstract
    Quantum-Gas Microscopes - Quantum-Simulation with Single-Particle Access

    Ultracold atoms in well-controlled engineered environments in optical lattices are a versa-tile tool for quantum-simulation of strongly correlated quantum systems. The most recent developments in this field include quantum-gas microscopes [1], enabling single-lattice-site resolution and single-atom control [2]. Imaging of with single-atoms resolution has made it possible to directly observe bosonic and fermionic many-body quantum systems in an un-precedented way, giving access to, e.g., in-situ measurements of temperature and entropy distributions, direct observation of correlations and their spreading, or the build-up of en-tanglement. I will present how we achieved single-atom-resolved fluorescence imaging of fermionic potassium-40 atoms using electromagnetically-induced-transparency (EIT) coo-ling [3], and a new way of Raman gray-molasses cooling [4]. I will also report on our pro-gress towards the creation of fermionic Mott insulators and the study of strongly correlated fermionic quantum systems and their out-of-equilibrium dynamics.

  • 30.01.2018

    Prof. Dr. K. Hassouni (Université Paris, France) abstract
    Nanoparticles formation in non-equilibrium plasmas

    Dusty plasmas were observed and investigated since the early 20th century in the context of astrophysical sciences, the early eighties in the context of material processing plasmas and for more than two decades in the context of edge tokamak plasmas and their interaction with fusion reactor materials.
    Surprisingly, the physical mechanisms and collisional processes that lead to the formation of dust particles in plasmas received little attention during the last century. The situation changed with the strong increase of interest for nanomaterial processing and the advent of ITER project. As a matter of fact, dusty plasmas were considered as a promising tool for making and processing functional nanomaterials with unique properties for a variety of applications. On the other hand, the formation of dust particles in tokamak edge plasmas represents a major safety concern and motivated a large research effort with the aim to understand the phys-ical mechanism that lead to the formation of these particles and to propose a way to inhibit these mecha-nisms. (Read more in the attached abstract)

  • 06.02.2018

    Prof. Dr. Livio Narici, INFN (Italian National Institute for Nuclear Physics), Rome abstract
    Anomalous light flashes & other sensory illusions due to charged particles in space and hadrontherapy

    In 1952 an article appeared in Journal of Aviation Medicinehypothesizing the poten-tial hazard of the cosmic rays in spaceflight. Dr. Tobias predicted that individual heavy ions passing through the retina might produce visual effects. In 1969, Edwin Aldrin reported mysterious visual stars and streaks during his lunar mission. This started a still ongoing interest on if and how cosmic radiation could modulate sen-sory and, more at large, brain activity, and if this could represent a functional health hazard. Many researches on ground (especially in the beginning of the 70’s) have been carried on, followed by a smaller number of space experiment (on the Apollo, Skylab, Apollo-Soyuz). More recently the interest revitalized with several investiga-tions both on ground (also on patients undergoing hadrontherapy) and in space. Since Tobias’ prediction we now know that not only heavy ions are producing sen-sory illusions, but also light ions, even protons. And there are also indications that all sensory channels and, possibly, also other brain activities, can be modulated by charged radiation. In this talk a brief history of the light flashes studies followed by a panorama of what is becoming evident about other sensory systems involvement will be presented. Experimental results from the ALTEA program about in vitro and in vivo (on animal models) investigations as well as about studies on humans (pati-ents and astronauts) will be presented.