Thickness dependence ofEB+-EB-2$\frac{{E}_{\text{B+}}-{E}_{\text{B-}}}{2}$(red open circles) after normalization by laser and THz absorption by PtSe2(see Supporting Information). The measurements were performed in transmission pumped from the backside with a laser pulse of 100 fs and a 2 mm ZnTe detector. The grey (green) solid lines are fits to the experimental data using Equation (1) andlsf= 3 nm (lsf= 2 nm).
