Extended Data Fig. 7: HX UPL from a 30° twisted bilayer WSe2 dual-gate transistor device.
a, Dependence of the HX UPL on out-of-plane electric-field strength Fz, showing Stark splitting of both the zero-phonon line and the trion. The neutral HX UPL in this case is 128 meV higher in energy than that of natural bilayer WSe2 (equivalent to a 60° twisted bilayer). b, Energy of the zero-phonon line as a function of the electric field, revealing a large permanent dipole moment of 0.56 e·nm and a small polarizability of 0.28 eV·nm2·V−2.
