Giant Magnetostriction from New Nanocomposite

Achievement date: 
2018
Outcome/accomplishment: 

Researchers at the Center for Translational Applications of Nanoscale Multiferroic Systems (TANMS), an NSF-funded Engineering Research Center (ERC) based at the University of California, Los Angeles (UCLA), have demonstrated the exceptional magnetostrictive properties of novel composite materials using new testing capabilities developed by partner institution Northeastern University (NU). The nanostructured composites are constructed in thin layers to blend the best properties of the constituent phases, which are made of iron-gallium (FeGa) and iron-nickel (NiFe) alloys.

Impact/benefits: 

The composites developed in this research exhibited magnetostrictive properties greater than the sum of FeGa and NiFe alone. The thin alternating layers demonstrate how innovative materials can be synthesized through nanoscale architecture. TANMS is currently utilizing these composites to develop multiferroic antennas, which can overcome fundamental limitations of electrically conductive antennas in high frequency applications.

Explanation/Background: 

Magnetostrictive materials like FeGa/NiFe composites are strained by magnetization and respond by changing shape or dimension. This effect can be combined with an electrostrictive material to convert that strain into an electrical signal. Magnetostrictive and electrostrictive materials are capable of converting kinetic energy to magnetic and electrical energies, respectively, and vice versa. The combination of both can be utilized to convert between magnetic and electrical energies. The conversion is a fundamental property of all antennas, and achieving it in this way is what fundamentally differentiates multiferroic antennas from their contemporary counterparts.

Most modern antennas are electrically conductive and rely on resonance to convert between magnetic and electrical energies. They must be sufficiently large enough for the frequencies at which they are designed to operate. In multiferroic antennas like the ones being developed by TANMS, operational frequencies are not dependent on size. This foundational property can be utilized to create extremely small and powerful antennas that can greatly influence the design of communications equipment, including many for commercial and defense applications. The magnitude of magnetostriction, which the TANMS team drastically increased in this research, is directly proportional to the performance of multiferroic antennas.