Dr. Flavio Y. Bruno presents a poster on the carrier density control of the surface 2DEG on SrTiO3 at the Workshop on Oxide electronics (WOE22) in Paris (Switzerland).
The complete poster is available here:
We investigated the influence of UV irradiation and oxygen exposure on the 2DEG found on the bare surface of (001)- and (111)- oriented STO. Using core level spectroscopy (XPS) and high-resolution angle resolved photoemission (ARPES) we show conclusively that this 2DEG arises from light induced oxygen vacancies and identify the dominant mechanism driving its formation. This opens a new route to tune the carrier density in oxide 2DEGs which we use to unravel systematic variations in the electronic structure that provide strong support for an interpretation in terms of quantum confinement.