Extended Data Fig. 10: Gate-dependent PL maps for different WSe₂/MoSe₂ heterobilayer devices.

a–l, High-excitation-power PL maps (a, d, g, j), low-excitation-power PL maps (b, e, h, k) and cross-cut spectra (c, f, i, l) of device 2 (a–c), device 3 (d–f), device 4 (g–i) and device 5 (j–l). Devices 2, 3 and 4 have approximately 60° twist angles; device 5 has an approximately 0° twist angle. The panels denote the incident laser power, the free interlayer exciton and trion emission (IX⁰ and IX^±) and their associated moiré exciton emission (MX⁰ and MX^±). A Stark shift is observed in the interlayer trion PL of device 5 because it is a single-gate device, in which charge injection induces an interlayer electric field, whereas devices 2–4 are dual-gate devices that allow us to inject carriers without applying an electric field to the heterobilayer. Sharp trion lines are observed in all of these devices, signifying the emergence of moiré trions. The sample temperature is T ≈ 5 K for the PL measurements of devices 2 and 3 and T ≈ 1.7 K for the PL measurements of devices 4 and 5.