LOCALIZATION AND THE METAL-INSULATOR TRANSITION - EXPERIMENTAL OBSERVATIONS

This article describes a series of experiments, mostly performed by the author and his collaborators over a period of 15 years, attempting to understand with the increase of disorder, the evolution from a Fermi liquid, to a state of localized electrons. During this period we relied heavily on theoretical advances, and the experiments were designed to test those theoretical models and challenge them in the regime of a highly correlated system. Experimentally, we were able to continuously tune through this regime into the insulating state and this allows measurements all the way from weak localization in two dimensions to strong localization and the insulating state. My efforts were focused mainly on electron transport and tunneling and will be described in this article. For this author, the work of my colleagues (and myself) during this period changed the way I think about electron transport.