We consider the localization of independent electron orbitals in double-layer two-dimensional electron systems in the strong magnetic-field limit. Our study is based on numerical Thouless number calculations for realistic microscopic models, and on transfer-matrix calculations for phenomenological network models. The microscopic calculations indicate a crossover regime for weak interlayer tunneling in which the correlation-length exponent appears to increase. Comparison of network model… Expand

We study relevant perturbations at the spin quantum Hall critical point using a network model formulation. The model has been previously mapped to classical percolation on a square lattice, and we… Expand

We report in this paper results of experimental and theoretical studies of transitions between different integer quantum Hall phases in two-dimensional electron systems, as well as the transition to… Expand

Two-dimensional periodically driven systems can host an unconventional topological phase unattainable for equilibrium systems, termed the Anomalous Floquet-Anderson insulator (AFAI). The AFAI… Expand

The nature of the transitions that occur between the quantized plateaux observed in the quantum Hall effect (QHE) have been classified as second order quantum phase transitions. These transitions… Expand