Allgemeines Physikalisches Kolloquium im Wintersemester 2012/2013
Ort: 48149 Münster, Wilhelm-Klemm-Str. 10, IG I, HS 2,
Zeit: Donnerstag, 15.11.2012 16:00 Uhr c.t.
Kolloquiums-Kaffee ab 15:45 Uhr vor dem Hörsaal
Matter wave interferometry with macromolecules: Spotlights on the foundations of quantum mechanics and molecule metrology
Prof. Dr. Markus Arndt, Fakultät für Physik, Universität Wien
The double slit experiment is probably the best known example of the quantum superposition principle. We here ask the question to what it extent this principle holds when we implement it with particles of very high mass and internal complexity. We discuss studies of the molecular wave motion based on text-book-like far-field experiments [1, 2], as well as more complex near-field interference arrangements [3-5].
This includes a new Kapitza-Dirac-Talbot-Lau interferometer with gratings aligned in position space as well as a Talbot-Lau interferometer in the time domain, based on pulsed laser light gratings. Both interferometers are universal tools for studying center-of-mass coherence with molecules, clusters and nanoparticles in the high-mass regime. To what extent may one test theories which suggest a non-linear extension to non-relativistic quantum mechanics to explain an objective or effective transition between quantum and classical physics?
Our recent experiments have shown that large complexes, composed of several hundred atoms, can be delocalized over hundred times their own size and still maintain quantum coherence in their center-of-mass motion over many milliseconds. Molecular interference allows us to pattern genuine molecular nanostructures on millimeter-wide molecular beams. It is, therefore, highly sensitive to all sorts of external perturbations but compatible with conservative force fields which do not measure the particle’s position.
We show how to use this for precise measurements of internal molecular properties, such as molecular electric polarizabilities, dipole moments, conformations and molecular dynamics [6].
- Arndt, M., et al., Wave-particle duality of C-60 molecules. Nature, 1999. 401(6754): p. 680-682.
- Juffmann, T., et al., Real-time single-molecule imaging of quantum interference. Nature Nanotechn., 2012. 7: p. 544.
- Gerlich, S., et al., Quantum interference of large organic molecules. Nature Communs 2011. 2: p. 263.
- Gerlich, S., et al., A Kapitza-Dirac-Talbot-Lau interferometer for highly polarizable molecules. Nature Phys., 2007. 3(10): p. 711-715.
- Hornberger, K., et al., Colloquium: Quantum interference of clusters and molecules. Rev. Mod. Phys., 2012. 84: p. 157-173
- Gring, M., et al., Influence of conformational molecular dynamics on matter wave interferometry. Phys.Rev. A, 2010. 81: p. 031604.
Einladender: Prof. Dr. Nikos Doltsinis
Im Auftrag der Hochschullehrer des Fachbereichs Physik
Prof. Dr. Nikos Doltsinis