Fig. 3.

(A) DFT band structure of AB-stacked ${\mathrm{M}\mathrm{o}\mathrm{T}\mathrm{e}}_2$/${\mathrm{W}\mathrm{S}\mathrm{e}}_2$ heterobilayer with displacement field D = 0, −0.25 (critical field), and −0.3 V/nm, showing gap reopening and band inversion. (B) Displacement field–dependent band gap at $\kappa$: The band gap reduces from 9 to 0 meV and then increases to 4 meV.