Drastic changes of the domain size in an ultrathin magnetic film

A general framework for the domain size in any ultrathin film with perpendicular magnetic anisotropy is here discussed. The domain structure is analyzed by using the classical theory taking into consideration the demagnetization field contribution to the domain wall energy. A sinusoidal model is con...

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Detalles Bibliográficos
Autores: Kisielewski, M., Maziewski, A., Zablotskii, V., Polyakova, T., García-Martín, José Miguel, Wawro, A., Baczewski, L. T.
Tipo de recurso: artículo
Fecha de publicación:2003
País:España
Institución:Consejo Superior de Investigaciones Científicas (CSIC)
Repositorio:DIGITAL.CSIC. Repositorio Institucional del CSIC
OAI Identifier:oai:digital.csic.es:10261/25117
Acceso en línea:http://hdl.handle.net/10261/25117
Access Level:acceso abierto
Palabra clave:Cobalt
Magnetic thin films
Perpendicular magnetic anisotropy
Magnetisation
Remanence
Magnetic hysteresis
Kerr magneto-optical effect
Magnetic force microscopy
Magnetic domain walls
Magnetic domains
Demagnetisation
Spin dynamics
Descripción
Sumario:A general framework for the domain size in any ultrathin film with perpendicular magnetic anisotropy is here discussed. The domain structure is analyzed by using the classical theory taking into consideration the demagnetization field contribution to the domain wall energy. A sinusoidal model is considered to describe the domain structure while approaching, in two different cases, the monodomain state with in-plane magnetization. The first case is realized applying a large enough in-plane magnetic field. The second one is obtained by decreasing the perpendicular magnetic anisotropy, which is connected in many ultrathin systems with the increase of film thickness. A change in the domain size of several orders of magnitude is obtained while approaching the magnetization reorientation region. The minimal stripe domain period p=8πlex2/d is calculated from the sinusoidal model, where lex is the exchange length and d is the thickness of the film. The range of possible domain size changes in ultrathin films is predicted. The domain size has been experimentally studied in a 1 nm Co film characterized by a square hysteresis loop. The investigations have been performed by polar Kerr based microscopy and magnetic force microscopy. The domain structure of two remnant states generated by applying an in-plane and a perpendicular magnetic field has been compared. Drastically, the smallest domain size has been observed for the former.