Project B12

We recently discovered the quantum metric nonlinear anomalous Hall effect (nl-AHE) in antiferromagnets preserving combined parity and time reversal symmetry (PT-AFs). It arises from electric field-induced Berry curvature and correlates with the antiferromagnetic order by reversing sign upon Néel vector inversion. Project B12 extends the nl-AHE to the optical regime, where it is predicted as a transverse to the Néel vector oriented DC photocurrent driven by dipole transitions. Besides demonstrating this new effect in PT -AFs, we will study thin films of AF Weyl semimetals and altermagnets with externally induced broken P-symmetry.