Publisher Correction: Direct imaging of the electron liquid at oxide interfaces

Correction to: Nature Nanotechnology https://doi.org/10.1038/s41565-017-0040-8, published online 5 February 2018.

In the version of this Letter originally published, in two instances in Fig. 1 the layers in the cross-sectional view of the (001) interface were incorrectly labelled: in Fig. 1b SrO⁺ should have read SrO⁰; in Fig. 1c LaO⁺, AlO₂^–, LaO⁺, TiO₂⁰, SrO⁺, TiO₂⁰ should have read LaO₃^3–, Al³⁺, LaO₃^3–, Ti⁴⁺, SrO₃^4–, Ti⁴⁺. In Fig. 3c the upper-right equation read –σ_s = –e/2a² but should have read –σ_s = e/2a² and in Fig. 3f the lower-right equation read –σ_s = –e/2√3a² but should have read σ_s = –e/2√3a². In addition, in the HTML version the affiliation 'Department of Materials Science and Engineering, Pohang University of Science and Technology (POSTECH), Pohang, Republic of Korea' was mistakenly listed as the present address of S.-Y.C. but should have been listed as an affiliation for K.S., B.P., J.K.L., S.-Y.C. and S.H.O. And, in the Supplementary Information file, the text 'small compared with the' was mistakenly added to the beginning of the title. These errors have now been corrected in the online version of the Letter.