Substrate effect on the magnetic microstructure of La0.7Sr0.3MnO3 thin films studied by magnetic force microscopy

Abstract

Colossal magnetoresistive (CMR) La 0.7 Sr 0.3 MnO 3 (LSMO) thin films have been grown under tensile strains on (100)-SrTiO 3 substrates and compressive strains on (100)-LaAlO 3 and (110)-NdGaO 3 substrates by pulsed laser deposition. Using magnetic force microscopy (MFM), a "feather-like" magnetic pattern, characteristic of films with an in-plane magnetization, is observed for films deposited on both SrTiO 3 and NdGaO 3 while a "bubble" magnetic pattern, typical of films with an out-of plane magnetization, is recorded for LaAlO 3 .We show that the shape of the magnetic pattern imaged by MFM is fully correlated to the easy direction of the magnetization in the film.Electronic mail : desfeux@univ-artois.fr

Out-of-plane magnetic domain structure in a thin film ofLa0.67Sr0.33MnO3onHouwman1, Maris2, Luca3 et al. 2008Phys. Rev. B271180View full textAdd to dashboardCite

“…This is generally interpreted as fitting in the model that the magnetization is largely in plane, due to the tensile strain of the film, induced by the STO substrate. This stands in contrast with films on LAO͑001͒ and NGO͑110͒, where there is compressive strain and therefore out-of-plane magnetization, giving rise to the typical mazelike domains 15,16 or bubble magnetic pattern, 14 respectively, stripe domains. 15 Here, we report on MFM measurements indicating that also for our LSMO films on STO ͑001͒ there is a significant out-of-plane magnetization.…”

“…The observed MFM pattern is generally described as having a featherlike pattern. [14][15][16] This is attributed to the magnetization being oriented predominantly in plane, because the film is in tensile strain in the ͓100͔ and ͓010͔ directions. Thus, there is currently no detailed knowledge about the magnetic domain structure of LSMO on STO ͑001͒.…”

“…MFM has been successfully used to detect the strong magnetic contrast on LSMO thin films grown on LaAlO 3 ͑001͒ ͑LAO͒ and NdGaO 3 ͑110͒ ͑NGO͒ substrates. [14][15][16] The films grown on LAO are in compressive strain in the ͓100͔ and ͓010͔ directions, forcing the magnetization vector out of plane. A clear mazelike pattern of up and down oriented domains is observed, consistent with a perpendicular anisotropy.…”

Microstructures and the corresponding magnetic properties of half-doped Nd0.5Sr0.5MnO3 films

“…It has been found that the easy axis magnetization for the manganite films is always along the direction of a tensile strain. 25,26 According to the XRD and the HREM analyses, the bottom A layer in this film has the out-of-plane tensile strain. Hence, the easy axis magnetization is normal to the applied magnetic field, which is a main reason for the observed low-field ZFC and FC M͑T͒ irreversibility.…”

Pulsed laser deposition of La1−xSrxMnO3: thin-film properties and spintronic applications

“…In addition, a high T C , good metallic conductivity, and atomically smooth interfaces are often essential for practical devices. Because strain control in thin LSMO films is vital for obtaining optimal properties, the effects of strain have been studied extensively [30][31][32] Other factors that control the magnetic and electrical transport properties of LSMO are film composition, oxygen stoichiometry and crystal orientation [34][35][36][37][38]. The composition and oxygen content mainly affect the saturation moment and the transition temperature, whereas lattice strain and film texture can also induce magnetic anisotropy [39,40].…”