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arXiv · 1006.0889

Magnetization dynamics of a CrO$_2$ grain studied by micro-Hall magnetometry

Pintu Das·Fabrizio. Porrati·Steffen Wirth·Ashna Bajpai·Michael Huth·Yuzo Ohno·Hideo Ohno·Jens Müller
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Abstract

Micro-Hall magnetometry is employed to study the magnetization dynamics of a single, micron-size CrO$_2$ grain. With this technique we track the motion of a single domain wall, which allows us to probe the distribution of imperfections throughout the material. An external magnetic field along the grain's easy magnetization direction induces magnetization reversal, giving rise to a series of sharp jumps in magnetization. Supported by micromagnetic simulations, we identify the transition to a state with a single cross-tie domain wall, where pinning/depinning of the wall results in stochastic Barkhausen jumps.

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Pintu Das, Fabrizio. Porrati, Steffen Wirth, Ashna Bajpai, Michael Huth, Yuzo Ohno, Hideo Ohno, Jens Müller. 2010-06-04. Magnetization dynamics of a CrO$_2$ grain studied by micro-Hall magnetometry. https://doi.org/10.1063/1.3467870

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