Untwinned YBa2Cu3O7-delta thin films on MgO substrates: A platform to study strain effects on the local orders in cuprates
Journal article, 2019
We have grown untwinned YBa2Cu3O7-delta (YBCO) films on (110) MgO substrates that were preannealed at high temperature in oxygen atmosphere. The annealing results in surface reconstruction with shallow facets, which induce the suppression of the YBCO twinning domains, and the preferential alignment of the CuO chains along one of the in-plane directions of the substrate. Because of the large mismatch between the in-plane lattice parameters of film and substrate, the strain induced by the MgO into the YBCO layer is strong and very peculiar. The YBCO film is compressed, with respect to the bulk, and presents a unidirectional buckling of the atomic planes, along the chains' direction, due to a deformation of the copper-oxygen octahedra. The YBCO films, which can be grown with thicknesses down to few unit cells and oxygen doping levels spanning most of the superconducting dome, are patterned into nanowires with dimensions down to 50 nm. The anisotropies due to the untwinning state are preserved in these structures; moreover, additional anisotropies appear in ultrathin structures where strain effects become more pronounced. Such untwinned and compressively strained films can therefore be used as a platform to study the interplay between strain and the various local orders in the normal state of YBCO.
Author
Riccardo Arpaia
Polytechnic University of Milan
Chalmers, Microtechnology and Nanoscience (MC2), Quantum Device Physics
Eric Andersson
Chalmers, Microtechnology and Nanoscience (MC2), Quantum Device Physics
Alexei Kalaboukhov
Chalmers, Microtechnology and Nanoscience (MC2), Quantum Device Physics
Elsebeth Schröder
Chalmers, Microtechnology and Nanoscience (MC2), Quantum Device Physics
Edoardo Trabaldo
Chalmers, Microtechnology and Nanoscience (MC2), Quantum Device Physics
Regina Ciancio
Laboratorio Nazionale TASC
Goran Drazic
National Institute of Chemistry
Pasquale Orgiani
University of Salerno
Thilo Bauch
Chalmers, Microtechnology and Nanoscience (MC2), Quantum Device Physics
Floriana Lombardi
Chalmers, Microtechnology and Nanoscience (MC2), Quantum Device Physics
Physical Review Materials
24759953 (eISSN)
Vol. 3 11 114804Subject Categories
Inorganic Chemistry
Other Materials Engineering
Condensed Matter Physics
DOI
10.1103/PhysRevMaterials.3.114804