We study the electronic contribution to the nonlinear optical response of the α-T3 model. This model is
an interpolation between a graphene (α = 0) and dice (α = 1) lattice. Using a second-quantized formalism,
we calculate the first- and third-order responses for a range of α and chemical potential values as well as
considering a band gap in the first-order case. Conductivity quantization is observed for the first-order, while
higher-order harmonic generation is observed in the third-order response with the chemical potential determining
which applied field frequencies both quantization and harmonic generation occur at. We observe a range of
experimentally accessible critical fields between 102–106 V/m with dynamics depending on α, μ, and the applied
field frequency. Our results suggest an α-T3-like lattice could be an ideal candidate for use in terahertz devices.