Skip to main content
U.S. flag

An official website of the United States government

Official websites use .gov
A .gov website belongs to an official government organization in the United States.

Secure .gov websites use HTTPS
A lock ( ) or https:// means you’ve safely connected to the .gov website. Share sensitive information only on official, secure websites.

Defect Related Switching Field Reduction in Small Magnetic Particle Arrays



Michael J. Donahue, G Vertesy, Martha Pardavi-Horvath


An array of 42 m square, 3 m thick garnet particles has been studied. The strong crystalline uniaxial anisotropy of these particles results in the stable remanent state being single domain with magnetization parallel to the film normal. Magnetooptic measurements of individual particles provide distribution statistics for the easy-axis switching field Hsw, and the in-plane hard-axis effective anisotropy field, Heff, which induces the formation of a metastable stripe domain structure. Both Hsw and Heff are much smaller than the crystalline anisotropy field. Micromagnetic simulations show that the small Hsw cannot be attributed to shape anisotropy, but is consistent with smooth, localized reductions in the crystalline anisotropy caused by defects in either the particles or the substrate.
Journal of Applied Physics
No. 10


coercivity, micromagnetic modeling, small magnetic particles, switching field


Donahue, M. , Vertesy, G. and Pardavi-Horvath, M. (2003), Defect Related Switching Field Reduction in Small Magnetic Particle Arrays, Journal of Applied Physics, [online], (Accessed June 20, 2024)


If you have any questions about this publication or are having problems accessing it, please contact

Created May 15, 2003, Updated February 17, 2017