Dear all
Please be informed about the following QSIT Seminar.
With best regards, Ilona Blatter --------------------------------------------------- Date: Monday March 21, 2011 Time: 13:00 Place: ETH Science City, HPF G 6 Host: Tilman Esslinger
Quantum transport with matter-waves Philippe Bouyer Institut d'Optique, Palaiseau, France
The transport of quantum particles in non ideal material media (eg the conduction of electrons in an imperfect crystal) is strongly affected by scattering from impurities of the medium. Even for a weak disorder, semi-classical theories, such as those based on the Boltzmann equation for matter-waves scattering from the impurities, often fail to describe transport properties and full quantum approaches are necessary. The properties of the quantum systems are of fundamental interest as they show intriguing and non-intuitive phenomena that are not yet fully understood such as Anderson localization, percolation, disorder-driven quantum phase transitions and the corresponding Bose- glass or spin-glass phases. Understanding quantum transport in amorphous solids is one of the main issues in this context, related to electric and thermal conductivities. Ultracold atomic gases can now be considered to revisit the problem of quantum conductivity and quantum transport under unique control possibilities. Dilute atomic Bose-Einstein condensates (BEC) and degenerate Fermi gases (DFG) are produced routinely taking advantage of the recent progress in cooling and trapping of neutral atoms. Transport has been widely investigated in controlled potentials with no defects, for instance periodic potentials (optical lattices). Controlled disordered potentials can also be produced with various techniques such as the use of magnetic traps designed on atomic chips with rough wires, the use of localized impurity atoms, the use of radio-frequency fields or the use of optical potentials. This recently lead to the observation of the Anderson Localization of a BEC and the measurement of the diffusion coefficient of a 2D gas in the presence of disorder. I will also discuss the recent development towards the observation of AL in 3D with matter-waves. ---------------------------------------------------
ETH Zurich Dr. Ilona Blatter QSIT Coordinator Laboratory for Solid State Physics HPF E 17 Schafmattstrasse 16 8093 Zurich
ilona.blatter@phys.ethz.ch www.qsit.ethz.ch www.nccr-qsit.ethz.ch
Phone: +41 44 633 36 06 Home: +41 44 844 42 50