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Measuring Lateral Magnetic Structure in Thin Films Using Polarized Neutron Reflectometry

W. -T. Lee·S. G. E. te Velthuis·G. P. Felcher·F. Klose·T. Gredig·D. Dahlberg·B. V. Toperverg
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Abstract

Polarized neutron reflectometry (PNR) has long been applied to measure the magnetic depth profile of thin films. In recent years, interest has increased in observing lateral magnetic structures in a film. While magnetic arrays patterned by lithography and submicron-sized magnetic domains in thin films often give rise to off-specular reflections, micron-sized ferromagnetic domains on a thin film produce few off-specular reflections and the domain distribution information is contained within the specular reflection. In this paper, we will first present some preliminary results of off-specular reflectivity from arrays of micron-sized permalloy rectangular bars. We will then use specular reflections to study the domain dispersion of an exchange-biased Co/CoO bilayer at different locations of the hysteresis loop.

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W. -T. Lee, S. G. E. te Velthuis, G. P. Felcher, F. Klose, T. Gredig, D. Dahlberg, B. V. Toperverg. 2002-10-06. Measuring Lateral Magnetic Structure in Thin Films Using Polarized Neutron Reflectometry. https://doi.org/10.1016/s0921-4526(03)00195-9

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