Exotic magnetic anisotropy map in epitaxial La_(0.7)Ca_(0.3)MnO_(3) films on BaTiO_(3)
We report the observation between 40 and 120 K of anomalous magnetic hysteresis loops in thin epitaxial films of La_(0.7)Ca_(0.3)MnO_(3) grown on ferroelectric BaTiO_(3). These hysteresis loops display extremely unusual features: after switching at coercivity, the magnetization overshoots the eventu...
| Autores: | , , , |
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| Tipo de recurso: | artículo |
| Fecha de publicación: | 2011 |
| País: | España |
| Institución: | Universidad Complutense de Madrid (UCM) |
| Repositorio: | Docta Complutense |
| Idioma: | inglés |
| OAI Identifier: | oai:docta.ucm.es:20.500.14352/44550 |
| Acceso en línea: | https://hdl.handle.net/20.500.14352/44550 |
| Access Level: | acceso abierto |
| Palabra clave: | 537 Thin-films Tunnel-junctions Strain Magnetoresistance Heterostructures Temperature Dependence Stress. Electricidad Electrónica (Física) 2202.03 Electricidad |
| Sumario: | We report the observation between 40 and 120 K of anomalous magnetic hysteresis loops in thin epitaxial films of La_(0.7)Ca_(0.3)MnO_(3) grown on ferroelectric BaTiO_(3). These hysteresis loops display extremely unusual features: after switching at coercivity, the magnetization overshoots the eventual high-field value. We study the strains in the film and substrate with x-ray diffraction and propose a model of two magnetic moment populations with different magnetoelastic anisotropies. The relative weights of both populations can be estimated by comparison with twin samples of La_(0.7)Ca_(0.3)MnO_(3) films on nonferroelectric SrTiO_(3). We propose that the observed magnetization overshoots the result from differences in the magnetostriction balance as the applied magnetic field increases. The picture of a nonuniform strain field in La_(0.7)Ca_(0.3)MnO_(3) on BaTiO_(3), caused by the corrugation of the ferroelectric domains in the rhombohedric phase of BaTiO_(3), is compatible with the magnetic granular behavior observed in the temperature and field dependences of the magnetization as well as in the low temperature magnetoresistance exhibited by the epitaxial film. |
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