Enhanced Magneto-Optic Properties Using Polymer-Coated Magnetite Nanoparticles

Case ID:

Researchers at The University of Arizona's James C. Wyant College of Optical Sciences have developed a two-step process for creating Magneto-optical (MO) nanocomposites. First it forms a polymer shell on magnetite-nanoparticles though a surface polymerization process. It then chemically links the shell of each magnetite-nanoparticle to a host polymer matrix to embed the nanoparticles. The polymer shells on such particles prevent the nanoparticles from forming agglomerates and can be used to obtain and/or preserve a particular size dispersion of the nanoparticles. The resulting MO composite materials have a large MO response with tunable properties and can be readily processed to form useful devices.


Magneto-optical (MO) nanocomposites are a special subclass of nanocomposites that are capable of exhibiting strong magneto-optical behavior. These materials consist of magnetic nanoparticles that are embedded in, suspended in, or otherwise structurally associated with a “host material,” such as an organic polymer. It has been shown that the MO effect of such materials depends on both nanoparticle density and uniformity, but nanoparticle clustering, a common fabrication defect, often causes the MO effect to be significantly reduced. Thus, there is a need to improve the methods for producing nanocomposites, including MO nanocomposites, to reduce unwanted aggregations and/or clusters of the nanoparticles while still allowing controllable nanoparticle spacing and size for tuning nanocomposite properties.


  • Magneto-optic isolators, modulators or switches
  • High-sensitivity magnetic field sensors
  • Magnetic data storage media
  • Integrable optical isolators, polarizers and rotators


  • Enhanced tunable magneto-optical properties
  • Composite material can be readily fabricated

Status: issued U.S. patents #9,011,710 and #9,378,880

Patent Information:
Contact For More Information:
Richard Weite
Senior Licensing Manager, College of Optical Sciences
The University of Arizona
Lead Inventor(s):
Robert Norwood
Palash Gangopadhyay
Alejandra Lopez-Santiago