The network model and the integer quantum Hall effect
Chapter in Encyclopedia of Condensed Matter Physics, (2024) V1:567-V1:574
Abstract:
We review the network model for the integer quantum Hall effect. The model provides a simplified description of Anderson localization in this context. It represents non-interacting electrons moving in two dimensions under the combined influence of a strong magnetic field and a smooth disordered potential. In this setting, electron eigenstates form disorder-broadened Landau levels and their character varies with energy across the Landau level. States in both the low-energy and the high-energy tails of the Landau level are localized, with a spatial extent characterized by the localization length. At the center of the Landau level there is a transition between phases with different quantized values of the Hall conductance and the localization length is divergent. The network model captures universal features of this transition.Bifurcations in Inertial Focusing of a Particle Suspended in Flow Through Curved Rectangular Ducts
Springer Proceedings in Mathematics & Statistics Springer Nature 454 (2024) 667-683
Non-reciprocal active-matter: a tale of “loving hate, brawling love” across the scales
Europhysics news EDP Sciences 55:3 (2024) 12-15
Phase ordering in binary mixtures of active nematic fluids
Phys. Rev. E 110, 024607 (August 2024)
Abstract:
We use a continuum, two-fluid approach to study a mixture of two active nematic fluids. Even in the absence of thermodynamically-driven ordering, for mixtures of different activities we observe turbulent microphase separation, where domains form and disintegrate chaotically in an active turbulent background. This is a weak effect if there is no elastic nematic alignment between the two fluid components, but is greatly enhanced in the presence of an elastic alignment or substrate friction. We interpret the results in terms of relative flows between the two species which result from active anchoring at concentration gradients. Our results may have relevance in interpreting epithelial cell sorting and the dynamics of multi-species bacterial colonies.
Finite-Entanglement Scaling of 2D Metals
Physical Review Letters American Physical Society (APS) 131:26 (2023) 266202