Friday 28th June 2013 | |
Chair: Friedrich Aumayr | |
09:00-10:00 | PT: Fundamental physics with heavy ions Thomas Stoehlker (GSI Atomic Physics Division) |
Highly charged ions (HCI) combine extremely strong electromagnetic fields and a simple electronic structure which makes them an ideal testing ground for fundamental theories such as quantum mechanics, relativity and quantum electrodynamics (QED) in the domain of the strongest electromagnetic fields available for experimental investigation. In this contribution, an overview of the recent progress in the demanding experiments aiming at the investigation of QED in such strong and even critical fields will be given. The progress and developments in recent experiments aiming at precise determination of the radiative corrections for the ground state and first excited states in the heaviest hydrogen- and helium-like ions (U91+, U90+) will be discussed. Here the effects of QED are largest and even close to the Schwinger limit. For Li-like ions even higher accuracies with sensitivities to radiative corrections of second-order have been achieved. All of these x-ray based investigations are complemented by laser spectroscopy of the hyperfine-levels in high-Z one- and few-electron ions which turned out to be particularly challenging for theory. Here the magnetic sector of strong field QED can be investigated with high accuracy where a real breakthrough was achieved very recently. The long sought for the resonance in lithium-like Bismuth (Bi80+) has been found and measured for the very first time by laser spectroscopy. In addition high-accuracy measurements on cooled heavy ions in Penning traps have opened novel opportunities for fundamental tests of physics. The determination of the magnetic moment of the electron bound in highly charged ions is a sensitive test of the theory of bound-state quantum electrodynamics in the strong-field regime and enables highly accurate determination of fundamental constants such as the mass of the electron. Finally, an outlook regarding probing of the fundamental physics phenomena in (super) critical fields as well as possible studies of parity non-conservation effects in few-electron heavy ions will be given. | |
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Session 7a: T4 Photon induced processes Chair: Nina Rohringer | |
10:30-11:00 | IT: Using TRPES to explore nonadiabatic dynamics: from small heteroaromatic molecules to the GFP chromophore Helen Fielding (University College London) |
Efficient electronic relaxation following the absorption of ultraviolet light is crucial for the photostability of biological chromophores, so understanding the microscopic details of the decay pathways is of considerable interest. Here, we describe femtosecond time-resolved photoelectron spectroscopy (TRPES) experiments investigating the ultrafast intramolecular dynamics of aniline and pyrrole, from which we determine how their photostability arises from a subtle balance between dynamics on different electronically excited states and importantly between Rydberg and valence states. We also describe femtosecond TRPES experiments investigating the ultrafast excited state dynamics of the isolated green fluorescent protein (GFP) chromophore anion, from which we determine that the excited state dynamics in vacuo are remarkably similar to those of the isolated chromophore in solution. | |
11:00-11:30 | IT: Atomic and Molecular Physics with X-ray free electron lasers Peter Lambropoulos (University of Crete) |
I present an overview of the main developments and possible scenario for the underlying physical mechanisms, in the interaction of strong, short pulse XUV to hard X-ray radiation, with bound electrons, with emphasis on multiple ionization and non-linearity. | |
11:30-12:00 | IT: Ultrafast dynamics in postcollision interaction upon argon 1s photoionization Tatiana Marchenko (Université Pierre et Marie Curie) |
The dynamics of postcollision interaction between the ionic field and the photo- and Auger electrons upon 1s shell ionization of argon, is investigated by means of photoelectron-ion coincidence momentum imaging as well as with high-energy Auger electron spectroscopy. Theoretical analysis provides quantitative estimates for lifetimes of the intermediate ionic states involved in the Auger decay. | |
12:00-12:15 | CT: Femtosecond Time-Resolved Imaging of Torsion in a Chiral Molecule using PImMS Lauge Christensen (Aarhus University) |
T10-10-Christensen.pdf | |
12:15-12:30 | CT: Photoelectron Diffraction on Laser-Aligned Molecules Rebecca Boll (Max Planck Institute for Nuclear Physics) |
T4-1-Boll.pdf | |
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Session 7b: T15 Rydberg atoms and ultra-cold plasmas Chair: Tim Softley | |
10:30-11:00 | IT: Manipulating Rydberg atoms close to surfaces Frederic Merkt (ETH Zürich) |
11:00-11:30 | IT: Nonlinear optics with cold atomic Rydberg gases Thomas Pohl (Max-Planck-Institute for the Physics of Complex Systems) |
We discuss the propagation of light through a cold gas of Rydberg atoms with strong van der Waals interactions. The latter are shown to induce highly non-local, single-photon nonlinearities that open up viable routes for single-photon generation, photonic quantum computing, and the exploration of many-body phenomena with correlated photons. | |
11:30-11:45 | CT: Few-body interactions in cold Rydberg gases Patrick Cheinet (CNRS, Laboratoire Aimé Cotton, Orsay) |
T15-4-Cheinet.pdf | |
11:45-12:00 | CT: Investigation of radiative cooling of small metal cluster anions by laser-induced electron detachment Michael Lange (Max Planck Institute for Nuclear Physics) |
T13-14-Lange.pdf | |
12:00-12:15 | CT: Controlling isomerization and fragmentation of polyatomic molecules by laser-sub-cycle electron recollision Xinhua Xie (Photonics Institute, Vienna University of Technology) |
T8-30-Xie.pdf | |
12:15-12:30 | CT: The Baryon-Antibaryon Symmetry Experiment (BASE) Kurt Franke (Max Planck Institute for Nuclear Physics) |
T19-14-Franke.pdf | |
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12:30-15:00 | Poster session |
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Session 8a: T17 Degenerate quantum gases / T18 Cold ions, atoms and molecules Chair: Klaus Mølmer | |
15:30-16:00 | IT: Trapping molecules on a chip Gerard Meijer (Fritz Haber Institute of the Max Planck Society) |
In this presentation, I will report on the trapping of neutral, dipolar molecules on a chip using direct loading from a supersonic beam. Upon arrival above the chip, the molecules are confined in electric field traps that move along with the molecular beam, i.e., at a velocity of several hundred meters per second. An array of these moving traps can be brought to a complete standstill over a distance of only a few centimetres. Rotational and vibrational excitation as well as two-dimensional spatial imaging of the molecules trapped on the chip has been demonstrated. | |
16:00-16:15 | CT: Resonances in ultracold collisions confined by atomic traps Vladimir Melezhik (Bogoliubov Laboratory of Theoretical Physics, Joint Institute for Nuclear Research) |
T2-13-Melezhik.pdf | |
16:15-16:30 | CT: Testing general relativity in space with atomic clocks: ACES mission Christine Guerlin (Laboratoire Kastler Brossel, ENS, Paris) |
T19-16-Guerlin.pdf | |
16:30-16:45 | CT: New Frontiers in Atomic, Molecular, and Cluster Science with the New Seeded Free Electron Laser FERMI@ELETTRA Oksana Plekan (Sincrotrone Trieste S.C.p.A. di interesse nazionale) |
T10-1-Plekan.pdf | |
16:45-17:00 | CT: Static trapping of molecules in a traveling wave decelerator Thomas Wall (VU University Amsterdam) |
T18-7-Wall.pdf | |
17:00-17:15 | CT: Towards an antihydrogen beam production by using a cusp trap Naofumi Kuroda (University of Tokyo) |
T19-15-Kuroda.pdf | |
17:15-17:30 | CT: Temperature Dependence of SF6- Auto-Detachment Rates Hilel Rubinstein (Weizmann Institute of Science) |
T7-2-Rubinstein.pdf | |
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Session 8b: T12 Biomolecules / T4 Photon Induced Processes Chair: Birgitta Whaley | |
15:30-16:00 | IT: Quantum effects in photosynthesis Alexander Eisfeld (Max-Planck-Institute for the Physics of Complex Systems) |
In photosynthetic complexes the energy of the absorbed light is transported via resonant electronic excitation transfer along assemblies of (bacterio)chlorophyll molecules. I will treat this transfer of electronic excitation using a fully quantum mechanical approach, focusing on the appearance of quantum coherences between the chlorophylls and their decoherence caused by the environment. Finally I will discuss in how far these coherences can be reproduced in a purely classical description. | |
16:00-16:30 | IT: From biological photoreceptors to the design of biomimetic molecular devices Massimo Olivucci (University of Siena) |
In the past multi-configurational quantum chemical computations have been employed to investigate spectroscopic, thermal and photochemical properties of visual pigments. Here we show how the same computational technology can nowadays be used to design, characterize and ultimately, prepare light-driven molecular switches which mimics the photophysics of the visual pigment rhodopsin. These artificial systems display light-induced ground state coherent vibrational motion similar to the one detected in rhodopsin and could potentially be engineered to undergo light-driven "continuos" rotary motion with a period approaching the picosecond time scale. | |
16:30-16:45 | CT: Dual photoresponse of isolated biological chromophores Anastasia Bochenkova (Aarhus University) |
T12-7-Bochenkova.pdf |