2014/02/17 by D A Mota, D. A. Mota, Y. Romaguera Barcelay +27
Materials Science · Physics and Astronomy · #Brillouin zone #Coercivity #Electrical resistivity and conductivity #Electronic and Structural Properties of Oxides #Magnetic and transport properties of perovskites and related materials #Magnetic domain #Magnetization #Magnetoresistance #Multiferroics and related materials #Phase (matter) #Phase transition #Thin film #cond-mat.mtrl-sci #cond-mat.str-el
paper · pdf · doi:10.1088/0022-3727/47/43/435002
15 pages, 9 figures
arxiv created 2014/02/17 · openalex publication_date 2014/10/03 · arxiv updated 2015/06/18 · openalex created_date 2016/06/24 · openalex updated_date 2026/08/05
Epitaxial La 0.7 Sr 0.3 MnO 3 (LSMO) thin films, with different thicknesses ranging from 20 to 330 nm, were deposited on (1 0 0)-oriented strontium titanate (STO) substrates by pulsed laser deposition, with their structure and morphology characterized at room temperature. The magnetic and electric transport properties of the as-processed thin films reveal an abnormal behaviour in the temperature dependent magnetization M ( T ) below the antiferrodistortive STO phase transition ( T STO ), and also an anomaly in the magnetoresistance and electrical resistivity close to the same temperature. Films with thickness ≤100 nm show an in-excess magnetization and pronounced changes in the coercivity due to the interface-mediated magnetoelastic coupling with antiferrodistortive domain wall movement occurring below T STO . However, in thicker LSMO thin films, an in-defect magnetization is observed. This reversed behaviour can be understood with the emergence in the upper layer of the film, of a columnar structure needed to relax the elastic energy stored in the film, which leads to randomly oriented magnetic domain reconstructions. For enough high-applied magnetic fields, as thermodynamic equilibrium is reached, a full suppression of the anomalous magnetization occurs, wherein the temperature dependence of the magnetization starts to follow the expected Brillouin behaviour.