BACKGROUND:  Giant Magnetoresistance (GMR) technology utilizes two or more magnetic thin films separated by a nonmagnetic layer to manipulate spin-dependent scattering of the conduction of electrons. In the zero-field state, the magnetization of adjacent magnetic layers are antiparallel, but under an applied external field, the magnetization of adjacent layers align and reduce magnetic scattering, thereby significantly reducing the resistance. GMR technology is used extensively in the read heads of hard drives and has many applications in electronic devices, data storage, and biological detection or drug delivery.

INNOVATION:  The fabrication process of the traditional metallic GMR is expensive due to the preparation of the magnetic thin films and complex packaging steps. Furthermore, due to the nature of the metallic layers, the structural integrity of traditional GMR sensors is severely limited. The technology developed at UCLA uses a novel fabrication method to easily and cost-effectively manufacture GMR sensors using flexible polymer nanocomposites that can directly interface with harsh environments without further packaging.

POTENTIAL APPLICATIONS:  Flexible polymer GMR sensors have great potential in hard drives and other magnetic data storage, biological detection or drug delivery, magnetic recording, and rotational sensing in automotive systems.

ADVANTAGES

• A simple and cost-saving fabrication process enabling large-scale commercial GMR sensor fabrication.
• Flexible of polymer films over the brittleness of metallic thin films
• The polymer can interface directly with harsh environments, eliminating the need for complex and expensive packaging steps

Reference: UCLA Case No. 2007-341