Floquet Engineering of Spin‐Valley Selective Transport in Jacutingaite

Abstract

We study electron transport through a monolayer jacutingaite () tunnel junction in which only the barrier is irradiated by off‐resonant circularly polarized light, while the leads remain undriven. In the high‐frequency regime, the driven barrier reduces to an effective static Dirac Hamiltonian with a photon‐dressed, valley‐dependent mass term. A staggered sublattice potential and a substrate‐induced exchange field provide additional tunable mass terms. Using scattering theory, we compute spin‐ and valley‐resolved transmission and reflection, as well as the Landauer conductance. Photon dressing shifts the barrier Dirac masses with opposite signs in the () valleys and induces a splitting of the propagation thresholds. The finite barrier then produces channel‐dependent Fabry–Pérot‐type interference through the phase . We find broad parameter windows with near‐perfect valley filtering () and substantial spin polarization (). The dominant spin and valley polarizations can be switched by tuning the drive amplitude , , and .