Atomic-scale identification of novel planar defect phases in heteroepitaxial YBa$_2$Cu$_3$O$_{7-δ}$ thin films

Nicolas Gauquelin; Hao Zhang; Guozhen Zhu; John Y. T. Wei; Gianluigi A. Botton

paper

Atomic-scale identification of novel planar defect phases in heteroepitaxial YBa $_{2}$ Cu $_{3}$ O $_{7 - δ}$ thin films

arXiv:1710.10667

Abstract

We have discovered two novel types of planar defects that appear in heteroepitaxial YBa $_{2}$ Cu $_{3}$ O $_{7 - δ}$ (YBCO123) thin films, grown by pulsed-laser deposition (PLD) either with or without a La $_{2/3}$ Ca $_{1/3}$ MnO $_{3}$ (LCMO) overlayer, using the combination of high-angle annular dark-field scanning transmission electron microscopy (HAADF-STEM) imaging and electron energy loss spectroscopy (EELS) mapping for unambiguous identification. These planar lattice defects are based on the intergrowth of either a BaO plane between two CuO chains or multiple Y-O layers between two CuO $_{2}$ planes, resulting in non-stoichiometric layer sequences that could directly impact the high- $T_{c}$ superconductivity.

Atomic-scale identification of novel planar defect phases in heteroepitaxial YBa2​Cu3​O7−δ​ thin films

Abstract

Atomic-scale identification of novel planar defect phases in heteroepitaxial YBa $_{2}$ Cu $_{3}$ O $_{7 - δ}$ thin films