Barrier tunneling for the dice lattice under linearly-polarized light

We have investigated electron tunneling across a square barrier under external off-resonance dress-
ing fields in α-T₃ lattices with variable interatomic coupling parameter α which yields the dice lattice
limit (or T₃ material) when α = 1. Our results show strong dependence on both the parameter α
and the polarization of the imposed irradiation. In the absence of the irradiation, the low-energy
pseudospin-1 Dirac-Weyl Hamiltonian which gives an energy spectrum consisting of a pair of Dirac
cones and a dispersionless ( at) band in the K and K′ valleys is employed for these calculations.
For the case of linearly-polarized dressing field, an asymmetric, or non-head on Klein tunneling has
been discovered. We explore the dependence of Klein tunneling through rectangular electrostatic
barriers as the irradiation intensity varies continuously. However, complete transmission is no longer
observed for α ≠ 1 under all types of incident light polarization.