Accession Number:

ADA564193

Title:

Producing Three Dimensional Nanostructured Magnetic Materials for Novel Magnetic Devices

Descriptive Note:

Final rept. 1 Dec 2008-30 Nov 2011

Corporate Author:

CALIFORNIA UNIV RIVERSIDE

Personal Author(s):

• Garay, Javier E.

Report Date:

2012-02-22

Pagination or Media Count:

4.0

Abstract:

We have produced large sized 3D magnetic nanocomposites using a current activated pressure assisted densification CAPAD. We were successful in producing dense nanocrystalline 100 nm average grain size materials based on iron oxides ferrites, rare earth oxides and silicon We have demonstrated magnetic coupling leading to exchange bias in large nanocrystalline iron oxides. Additionally we can orient the magnetically coupled grains causing their magnetic properties to be highly anisotropic. These materials have promising applications in magnetoresistance based devices as well as permanent magnets. The rare earth oxides are transparent to visible light and cause very high Faraday rotations. The Verdet constant of these nanocrystalline materials is more than twice that of the state of the art Faraday rotation materials. We also used the CAPAD technique to show that the thermal conductivity in of polycrystalline silicon can be controlled using nanostructure.

Descriptors:

• *MAGNETIC DEVICES
• FARADAY EFFECT
• FERRITES
• MAGNETIC FIELDS
• OXIDES
• POLYCRYSTALLINE
• RARE EARTH COMPOUNDS
• SILICON
• THERMAL CONDUCTIVITY

Subject Categories:

• Electricity and Magnetism

Distribution Statement:

APPROVED FOR PUBLIC RELEASE