The interfaces between some perovskite oxide insulators show spectacular electronic properties, originating from the formation of an electron gas. The spatial extent of the electron gas is still under debate. Conducting tip atomic force microscopy is now used to show that, depending on the growth conditions, the high-mobility electron gas can extend to hundreds of micrometres or to just a few nanometres from the interface.
- M. Basletic
- J.-L. Maurice
- A. Barthélémy
