Ab-initio simulations have shown that the bandgap of WSe2 can be modulated through the application of an external electric field [link]. In the case of bilayer and trilayer WSe2, authors show results for unreasonably large electric field (larger that critical electric field of most of dielectrics i.e., 10 MV/cm). Results on 4L WSe2 are instead interesting and could lead to an exploitation in electronic devices.

[Picture extracted from the article]