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Fabrication of Magnetic Nanostructures on Silicon Nitride Membranes for Magnetic Vortex Studies Using Transmission Microscopy Techniques
Published on: July 2, 2018
Los dominios magnéticos a nanoescala en los imanes mesoscópicos
1M. Hehn, K. Ounadjela, J.-P. Bucher, Institut de Physique et Chimie des Materiaux de Strasbourg, 23 rue du Loess, 67037 Strasbourg Cedex, France. F. Rousseaux and D. Decanini, L2M/CNRS, 196 Avenue Henri Ravera, 92225 Bagneux, France. B. Bartenlian and C. Chappert, Institut d'Electronique Fondamentale, Universite Paris-Sud, 91405 Orsay Cedex, France.
Science (New York, N.Y.)
|June 21, 1996
Resumen
Los patrones de dominio magnético en los nanodotes de cobalto difieren de las películas continuas. La geometría de los nanopuntos controla estos intrincados patrones, influyendo en las propiedades magnéticas y la inversión de la magnetización.
Área de la Ciencia:
- Ciencia de los materiales Ciencia de los materiales.
- Física de la materia condensada Física de la materia condensada
- Nanotecnología La nanotecnología es la nanotecnología.
Sus antecedentes:
- Los materiales nanoestructurados tridimensionales exhiben propiedades magnéticas únicas en comparación con las películas continuas.
- Comprender el comportamiento del dominio magnético en las nanoestructuras es crucial para el desarrollo de dispositivos magnéticos avanzados.
Objetivo del estudio:
- Para investigar la influencia de la geometría en los patrones de dominio magnético en puntos de cobalto de submicrometro.
- Para explorar la sintonizabilidad de la anchura del dominio magnético mediante la alteración del grosor del nanodot.
- Para analizar el papel de estas configuraciones de dominio en el proceso de inversión de la magnetización.
Principales métodos:
- Se empleó microscopía de fuerza magnética de alta resolución (MFM, por sus siglas en inglés) para estudiar nanopartículas de cobalto.
- Se fabricaron puntos de cobalto de tamaño submicrómetro con diferentes dimensiones geométricas.
- Se midieron los bucles de histeresis promediados en conjunto para observar la inversión de la magnetización.
Principales resultados:
- Se observaron intrincados patrones de dominio magnético, incluyendo anillos concéntricos y espirales con configuraciones de vórtice.
- Se descubrió que la anchura de los dominios magnéticos geométricamente restringidos era ajustable cambiando el grosor del punto.
- Se encontró que estas configuraciones específicas de dominio eran significativas durante el proceso de reversión de la magnetización.
Conclusiones:
- La geometría de los materiales magnéticos nanoestructurados dicta fundamentalmente su comportamiento en el dominio magnético.
- Las estructuras de dominio magnético sintonizables en nanodotes de cobalto ofrecen potencial para aplicaciones de dispositivos magnéticos controlados.
- Las configuraciones de dominio de vórtice juegan un papel clave en los mecanismos de reversión de la magnetización de estos nanodots.
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