Coherent Backscattering and Universal Fluctuations near the Localization Threshold*

 Bart van Tiggelen
CNRS/Laboratoire de Physique et Modélisation des Milieux Condensés
Université Joseph Fourier
Maison des Magistères
BP 166
F-38042 Grenoble Cedex 9
France
http://lpm2c.polycnrs-gre.fr/Themes/tiggelen/vanTiggelen.html

Coherent (or enhanced) backscattering (CBS) and Universal Conductance Fluctuationss (UCF) are two mesoscopic phenomena that have achieved great attention not only in electronic physics but also with classical waves. The theory for these phenomena has been well established in the eighties. In the present talk I will discuss first a novel theory for CBS near the mobility edge [1]. This theory predicts that the diffusion constant becomes spatially inhomogeneous, which in turn modifies the angular line profile of CBS. Secondly I will discuss theory and set-up of a recent succesfull attempt to observe UCF with microwaves, making explicit use of its electromagnetic polarization. The experiments where done at Queens College in Quasi-1D samples very close to the mobility edge (Thouless conductance g = 2.4)

References:
[1]. B.A. van Tiggelen, A. Lagendijk, and D.S. Wiersma, Phys. Rev. Lett. 84, 4341 (2000).
[2]. A. Chabanov, A.Z. Genack, N.P. Trégourès and B.A. van Tiggelen, in prepararion.

* Collaborators: Ad Lagendijk (Universty of Twente, the Netherlands), Diederik Wiersma (LENS-Florence, Italy), Azriel Genack and Andrey Chabanov (Queens College, New York USA)