Spin and orbital Ti magnetism at LaMnO3/SrTiO3 interfaces

In systems with strong electron-lattice coupling, such as manganites, orbital degeneracy is lifted, causing a null expectation value of the orbital magnetic moment. Magnetic structure is thus determined by spin–spin superexchange. In titanates, however, with much smaller Jahn–Teller distortions, orb...

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Detalles Bibliográficos
Autores: Garcia Barriocanal, Javier, Cezar, J. C., Bruno, Flavio Yair, Thakur, P, Brookes, N. B., Utfeld, C., Rivera Calzada, Alberto Carlos, Giblin, S. R., Taylor, S. W., Duffy, J. A., Dugdale, S. B., Nakamura, T., Kodama, K., León Yebra, Carlos, Okamoto, S., Santamaría Sánchez-Barriga, Jacobo
Tipo de recurso: artículo
Fecha de publicación:2010
País:España
Institución:Universidad Complutense de Madrid (UCM)
Repositorio:Docta Complutense
Idioma:inglés
OAI Identifier:oai:docta.ucm.es:20.500.14352/44760
Acceso en línea:https://hdl.handle.net/20.500.14352/44760
Access Level:acceso abierto
Palabra clave:537
Multidisciplinary sciences
Electricidad
2202.03 Electricidad
Descripción
Sumario:In systems with strong electron-lattice coupling, such as manganites, orbital degeneracy is lifted, causing a null expectation value of the orbital magnetic moment. Magnetic structure is thus determined by spin–spin superexchange. In titanates, however, with much smaller Jahn–Teller distortions, orbital degeneracy might allow non-zero values of the orbital magnetic moment, and novel forms of ferromagnetic superexchange interaction unique to t_2g electron systems have been theoretically predicted, although their experimental observation has remained elusive. In this paper, we report a new kind of Ti^3+ ferromagnetism at LaMnO_3/SrTiO_3 epitaxial interfaces. It results from charge transfer to the empty conduction band of the titanate and has spin and orbital contributions evidencing the role of orbital degeneracy. The possibility of tuning magnetic alignment (ferromagnetic or antiferromagnetic) of Ti and Mn moments by structural parameters is demonstrated. This result will provide important clues for understanding the effects of orbital degeneracy in superexchange coupling.