Article

Critical state of the Anderson transition: between a metal and an insulator.

Laboratoire Kastler Brossel, UPMC-Paris 6, ENS, CNRS; 4 Place Jussieu, F-75005 Paris, France.
Physical Review Letters (Impact Factor: 7.73). 08/2010; 105(9):090601. DOI: 10.1103/PHYSREVLETT.105.090601
Source: arXiv

ABSTRACT Using a three-frequency one-dimensional kicked rotor experimentally realized with a cold atomic gas, we study the transport properties at the critical point of the metal-insulator Anderson transition. We accurately measure the time evolution of an initially localized wave packet and show that it displays at the critical point a scaling invariance characteristic of this second-order phase transition. The shape of the momentum distribution at the critical point is found to be in excellent agreement with the analytical form deduced from the self-consistent theory of localization.

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