We propose to continue our low-temperature research program on disordered mesoscopic systems and specially designed nanostructures. The first part, which concerns quantum interference effects in transport processes, will comprise studies of narrow-bandgap mesoscopic conductors and superlattice effects. In addition, we envisage work on single-electron charging in a vertical tunneling structure, probing the question of "coulomb blockade" vs quantized-flux conductance effects, and developing a split-gate, electrostatic AB device. Unique advances in materials fabrication and processing have given accessibility to entirely new experimental systems. This work aims at a comprehensive understanding of how quantum phase interference and correlated transport effects evolve in complex disordered systems. It bears directly upon current and near-future efforts to develop powerful new devices for measurement and control in science and industry.
