2010/10/07 by A. Bussmann‐Holder, Bussmann-Holder, Annette, K. A. Müller +2
Materials Science · Physics and Astronomy · #Electronic and Structural Properties of Oxides #FOS: Physical sciences #Magnetic and transport properties of perovskites and related materials #Physics of Superconductivity and Magnetism #Superconductivity (cond-mat.supr-con)
paper · pdf · doi:10.48550/arxiv.1010.1377
openalex publication_date 2010/10/07 · openalex created_date 2022/09/14 · openalex updated_date 2026/07/28
The discovery of high temperature superconductivity in cuprates was possible\nonly through an intimate knowledge of perovskite oxides which have been\nsynthesized and characterized for decades at the IBM in the Z "urich\nlaboratoty. Especially SrTiO3 and LaAlO3 have been in the focus at IBM as was\npresented in Volume 1 of a series [1]. Probably for the first time detailed\nmicroscopic investigations of the local properties of these compounds have been\nobtained by studying by means of EPR the surroundings of transition metal\nimpurities in these materials. These experiments enabled the identification of\nthe order parameter of the structural instability observed in these oxides.\nHowever, the idea to search for superconductivity came later motivated by\ntheoretical considerations that metallic hydrogen could become superconducting\nat high temperatures. Since SrTiO3 is an insulator it was thought that the\nimplantation of hydrogen would render it metallic and eventually also\nsuperconducting. This approach failed since the carrier density remained always\ntoo small. In sequence it was then tried to achieve a metallic state in oxide\nperovskites by varying their composition which was in so far promising as\nreduced SrTiO3 exhibits superconductivity at 0.3K [2]. Furthermore it was\nsubsequently shown [3] that Tc can be enhanced to 1.2K by doping SrTiO3 with\nNb. In spite of the fact that Tc was far below values achieved in A15\ncompounds, a remarkable observation was connected with the Nb doped perovskite,\nnamely for the first time long before predicted two-gap superconductivity was\nrealized here.\n