Coordinators: Leticia Fernanda Cugliandolo, Lev Ioffe, Zvi Ovadyahu, Michael Pollak
Scientific Advisors: Miguel Ortuño, Clare Yu
The program focuses on out-of-equilibrium properties of strongly disordered interacting quantum systems. A conspicuous representative here is the electron-glass - an Anderson-localized system with Coulomb interactions. Due to the light mass of the electron, quantum effects may become crucially important in determining the dynamical properties of the electron glass, which distinguishes it from many other glasses that remain essentially classical at experimental temperatures. The glass, being a non-ergodic system, is not directly amenable to conventional methods of statistical physics, thus posing a challenge to a detailed understanding. While much progress has been made, many open questions remain, and it is hoped that the program will contribute significantly to resolving some of these.
Many problems of the electron glass physics are shared by other systems and these are included in the program. Some such problems are many-body-localization, dephasing in quantum-devices, dissipative coupling to a heat-bath, and noise and fluctuations in quantum systems. For example, dissipation and quantum effects seem to control the relaxation-dynamics of the electron-glasses, and they are important ingredients in the physics that governs coherence in Josephson devices. The basic ingredients of the electron glass (i.e., disorder, interaction, and quantum tunneling) lead in the weak-coupling regime to the so-called many-body localization and in the low-density regime to the Wigner glass. Noise measurements employed as a diagnostic tool by researchers in the different fields yield useful information on the nature of the fluctuators in electron-glasses, and help in tracking down sources of de-coherence in Josephson qubit devices. Coupling to a heat-bath (which may be the electron system itself) plays a significant role in all the above phenomena, and the elucidation of these issues will be an important part of the program.
Advances in the subject result from a blend of experiment, analytical theory and computer simulation, and the program aims to bring together individuals from all three approaches. Discussions among them shall hopefully bring about clarification of some poorly understood aspects of the subject and facilitate collaborations.
Specific subjects to be addressed include:
- Non-equilibrium properties of electron-glasses; glassy effects reflected in conductivity, aging and slow relaxation.
- Similarities and differences between various glasses, particularly ‘structural’ TLS and electron glasses, ways to distinguish between intrinsic and extrinsic electronic glasses
- Noise in electron glasses and Josephson junctions; noise and mesoscopic effects as diagnostic tools.
- Interactions and localization, many-body localization, collective delocalization.
- Numerical simulations of classical and quantum electronic glasses.
- Wigner glass.
- Glassy features in strongly correlated systems (e.g., high-Tc compounds).
Associated with this program will be a conference: “Out of Equilibrium Quantum Systems” to be held August 23-27, 2010. Further information will be posted here when it becomes available.