Resistance fluctuations near integer quantum Hall transitions in mesoscopic samples

We perform first-principles simulations to study the resistance fluctuations of mesoscopic samples, near transitions between quantum Hall plateaus. We use six-terminal geometry and sample sizes similar to those of real devices and calculate the Hall and longitudinal resistances using the Landauer formula. Our simulations recapture all the observed experimental features. We then use a generalization of the Landauer-Büttiker model, based on the interplay between tunneling and chiral currents, to explain the three regimes with distinct fluctuations observed, and identify the central regime as the critical region.