Condensed Matter Seminar Series

Integer Quantum Hall Transition: Interaction and Multifractality

Soumya Bera

Institut Neel, Grenoble France

Thursday April 26,  11:00 am,  Room 298,  Physics Building

Abstract:  Understanding the effect of the electron-electron interaction is one of the most challenging problems in the context of Anderson localization and the quantum Hall effect. In our study, we address this question by doing a perturbation theory in the interaction near the non-interacting fixed point of the integer quantum Hall transition. In each order, diagrams appear which contain correlation functions characterizing the fluctuation properties of wavefunctions at the (non-interacting) critical fixed point. We present a numerical study based on the Chalker-Coddington network, in which we determine quantitatively the subleading multifractal exponents of the salient wavefunction correlators, which dominates the interaction correction.