This title appears in the Scientific Report : 2019 

Topotactic transition mechanisms in SrCoO$_{2.5+𝑥}$ films
Schöffmann, Patrick (Corresponding author)
Pütter, Sabine / Sarkar, Anirban / Syed Mohd, Amir / Waschk, Markus / Bhatnagar, Tanvi / Zakalek, Paul / Brückel, Thomas
Heinz Maier-Leibnitz Zentrum; MLZ
Streumethoden; PGI-4
Physik Nanoskaliger Systeme; ER-C-1
Streumethoden; JCNS-2
DPG-Frühjahrstagung der Sektion Kondensierte Materie, Regensburg (Germany), 2019-03-31 - 2019-04-05
Conference Presentation
Jülich Centre for Neutron Research (JCNS)
Quantum Condensed Matter: Magnetism, Superconductivity
Controlling Collective States
Strontium cobaltite (SrCoO3−𝛿) exists in two topotactic phases, depending on the oxygen content. SrCoO3 is a ferromagnetic metal (T𝐶=305K) with perovskite structure while SrCoO2.5 is an antiferromagnetic insulator(T𝑁=570K) with brownmillerite structure. Because of the multivalent Co states and high oxygen mobility it is a promising material for energy and information applications [1]. To control the oxygen content, several possibilites exist. We focus on annealing in oxidising conditions and applying variable strain with a piezoelectric substrate to the film. We grow thin films of SrCoO2.5 by molecular beam epitaxy on various substrates including a piezoelectric with a conducting buffer layer. To be able to transfer strain from the substrate to the film, a highsample quality and epitaxy is mandatory, thus we present the results of the film growth and quality, as well as first results of the magnetic characterisation by SQUID and neutron reflectometry. [1] H. Jeen et al., Nature Materials 12, 2013