YBa2Cu3O7-δ single crystals revisited: Scanning probe data on very pure samples grown in BaZrO3 crucibles

Article Article scientifique Article YBa2Cu3O7-δ single crystals revisited: Scanning probe data on very pure samples grown in BaZrO3 crucibles eng 1998 author Hubler Ulrich 65172 author Jess P. author Lang H.P. author Erb Andréas 91616 author Walker Eric 24664 author Regier M. author Schild D. author Halbritter J. author Güntherodt H.-J. S1219-S1222 10.1007/PL00022824 0947-8396 Cu3O7-δ (YBCO) single crystals grown in BaZrO3 crucibles by scanning and friction force microscopy (SFM, FFM) as well as by scanning tunneling microscopy (STM) and angle resolved X-ray photo-electron spectroscopy (ARXPS). By STM and SFM, clean stepped terraces are observed on as-grown crystals. Friction contrast, however, implies the presence of different materials, presumably traces of flux. After oxidation of the YBCO crystals, particles of 10 to 100 nm in size appear on the surface. Their number per unit area increases with time when the crystal is stored in air. Complementary information on such aged YBCO surfaces is provided by ARXPS. These data reveal 3 nm of mainly BaCO3 and CuO on top of the YBCO matrix and suggest a very slow aging rate of the crystals, which is 20 times slower than for epitaxial thin films. The superconducting energy gap has been determined on fresh crystals by scanning tunneling spectroscopy (STS) at 4.6 K as 2Δ≈30 meV. By spatially resolved tunneling spectroscopy the vortex lattice in a magnetic field of 4 T has been imaged. The inter-vortex distance amounts to 20±2 nm. Dewey 500.2 33 Département de physique de la matière quantique 131 false Applied Physics A: Materials Science and Processing 66 Supplement 1 b8d9ae6e-2727-4057-a711-ca6e63e68336 Article (Published version) Public Hubler1998_Article_YBa2Cu3O7-δSingleCrystalsRevis.pdf 363965 application/pdf OA OTHER openAccess Faculté des sciences / Section de physique / Département de physique de la matière quantique

Title	Published in	Access level	OA Policy	Year	Views	Downloads

YBa₂Cu₃O_7-δ single crystals revisited: Scanning probe data on very pure samples grown in BaZrO₃ crucibles	Applied Physics A: Materials Science and Processing			1998	562	225

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Hubler, Ulrich