Abstract
For years, itinerant charge carriers in ferroelectric insulators were believed to completely quench ferroelectricity. Recent breakthroughs, however, demonstrated the existence of a novel class of quasi-two-dimensional polar metals with promising applications in nonvolatile electronics and spintronics. Here, by combining temperature-dependent magnetotransport measurements, optical second harmonic generation (SHG), resonant photoemission spectroscopy (ResPES), and X-ray absorption spectroscopy (XAS), we report on the properties of a BaTiO3-based oxide heterostructure, sustaining a persistent polar displacement in the BaTiO3 layer while supporting a two-dimensional electron gas. This suggests that the oxide heterostructure may operate as a polar metal system, paving the way for new developments in oxide-based electronics.
Funding Information
  • European Commission (101115190)
  • Ministero dell???Istruzione, dell???Universit?? e della Ricerca (2022TCJP8K, CUPB53C22004310006, IR0000015, P2022TCT72)
  • European Commission (101108695)
  • European Commission (M4C2)