2019/10/07 by A. Bussmann‐Holder, Bussmann-Holder, Annette, H. Keller +6
Materials Science · #Electronic and Structural Properties of Oxides #FOS: Physical sciences #Ferroelectric and Piezoelectric Materials #Magnetic and transport properties of perovskites and related materials #Materials Science (cond-mat.mtrl-sci)
paper · pdf · doi:10.48550/arxiv.1910.02748
openalex publication_date 2019/10/07 · openalex created_date 2025/10/10 · openalex updated_date 2026/07/28
Doped SrTiO3 becomes a metal at extremely low doping concentrations n and is\neven superconducting with the superconducting transition temperature adopting a\ndome-like shape with the carrier concentration. It is shown here within the\npolarizability model that up to a well-defined carrier concentration transverse\noptic mode softening takes place together with polar nano-domain formation\nwhich evidences inhomogeneity and a two-component type behavior with\nmetallicity coexisting with polarity. Beyond this region a conventional metal\nis formed where superconductivity as well as mode softening is absent. For this\nregime the effective electron-phonon coupling follows the superconducting\ntransition temperature. Effusion measurements as well as macroscopic and\nnanoscopic conductivity measurements indicate that the distribution of oxygen\nvacancies is local and inhomogeneous from which it is concluded that\nmetallicity stems from filaments which are embedded in a polar matrix as long\nas the carrier concentration is less than the critical one.\n