CPM Seminar
Coherent and Dissipative Transport in Aperiodic Media
Jean Bellissard
Georgia Institute of Technology
&
Institut
Universitaire de France
Electronic transport in aperiodic materials (ordered or disordered) might be
complex. The Mott hopping conductivity in Anderson insulators or the scaling
laws for the conductivity in quasicrystals are good examples of such a
complexity. Using the mathematical framework of Noncommutative Geometry
allows to write closed formulae without Bloch theory. Then using Analysis to
characterize spectral and transport properties, various characteristic
exponents are introduced to describe the coherent part of the transport
(quantum interferences). Dissipation can be introduced in various ways,
leading to an anomalous Drude formula, expressing the conductivity as a
scaling law in terms of the relaxation time. A discussion follows to show how
its relevance for quasicrystals. In a conclusion, some indication will be
given on how treating more accurately dissipation is being done.
Wednesday, August 4th 2004, 14:00
Ernest Rutherford Physics Building, R.E. Bell Conference Room (room 103)
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