Speaker
Description
The nonlinear Hall effect in quantum materials has attracted broad interest; yet most existing studies focus on the weak-field, perturbative regime.
Here we develop a nonperturbative approach based on nonequilibrium steady-state Green's functions for dc-field-driven lattice systems, with dissipation and interactions incorporated through self-energies beyond the constant relaxation-time approximation and interband transitions treated alongside their intraband counterparts.
Applied to a two-band semimetal model, our approach provides direct access to the strong-field Hall response beyond the nonperturbative crossover where the edge of the nonequilibrium distribution reaches Berry-curvature hot spots, a regime in which constant relaxation-time estimates and Berry curvature dipole calculations become unreliable.
We further demonstrate that interaction and electron-phonon self-energies within dynamical mean-field theory can substantially enhance the Hall signal.
Our framework enables quantitative simulations of nonequilibrium nonlinear Hall phenomena and provides guidance for strong-field transport experiments.