Extended Data Fig. 6: Visualization of the 2DEG electron density for higher charge.
Visualization of the 2DEG electron density in the STO substrate for ∆q = 1.5 e− (integrated from −0.7 eV to EF; yellow orbitals) and accumulated 2DEG charge for varying ∆q (modeling different light intensities). From this plot, one can extract the fraction of the additional charge that is accommodated in the two-dimensional electron gas (2DEG), which in this case amounts to approximately 0.95 e− (63%). For comparison, the corresponding values are ~0.19 e− (76%) and 0.36 e− (72%) for ∆q = 0.25 and 0.5 e−, respectively. Additionally, in our calculations, holes are treated as a homogeneous background distributed throughout the entire simulation cell. It should be noted that for such a large ∆q, finite-size effects become significant, that is, the actual 2DEG is expected to be more spatially extended than our simulation cell allows.
