Abstract

A new development in small-angle neutron scattering with polarization analysis allows us to directly extract the average spatial distributions of magnetic moments and their correlations with three-dimensional directional sensitivity in any magnetic field. Applied to a collection of spherical magnetite nanoparticles 9.0 nm in diameter, this enhanced method reveals uniformly canted, magnetically active shells in a nominally saturating field of 1.2 T. The shell thickness depends on temperature, and it disappears altogether when the external field is removed, confirming that these canted nanoparticle shells are magnetic, rather than structural, in origin.

Publisher

American Physical Society

Publication Date

5-21-2010

Publication Title

Physical Review Letters

Department

Physics and Astronomy

Document Type

Article

DOI

10.1103/PhysRevLett.104.207203

Keywords

Magnetic nanoparticles, Polarized neutron scattering

Document Version

published

Language

English

Format

text

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