The Hall coefficient of weakly interacting systems can be related to their density of effective charge carriers. However, in presence of strong correlations, one observes `Hall anomalies', i.e. abrupt changes in sign and magnitude of the Hall coefficient. We study two model problems- (i) the t-J model, and (ii) the hardcore boson model and calculate the Hall coefficient using a recently developed formula in terms of thermodynamic susceptibilities. The high temperature behaviour is calculated semi-analytically using high temperature expansions. The lower temperature behaviour is estimated using QMC computations. We show that in both cases, the Hall coefficient diagnoses the 'minority carriers' and the usual Fermi liquid-Boltzmann theory ideas become inapplicable.
Zoom Link: https://icts-res-in.zoom.us/j/99822052994?pwd=RHVQTXYwMjBPak1ITDdoNEovejdZQT09
Meeting ID: 998 2205 2994
Passcode: 080908