Fig. 1
From: Probing dopant segregation in distinct cation sites at perovskite oxide polycrystal interfaces
Distribution of charged defects and electrical potential near the surface. This figure shows the case of donor doping in a MO-type oxide crystal. \(\left[D_{M}^{\cdot}\right]\) and \(\left[ {V_M^\prime} \right]\) in the left diagram indicate the concentrations of donors and cation vacancies in the Kröger–Vink notation, respectively. The ϕ∞ in the right diagram also denotes the electrical potential in the bulk far from the surface. Strong segregation of donors and corresponding deficiency of cation vacancies in the space-charge layer is noted to compensate the excess surface charge. For more details, see Supplementary Note 1 and Supplementary Fig. 1
