MRI: Development of Full Vector Vibrating Sample Magnetometry for Materials Research and Education

Texas State University - San Marcos, San Marcos TX

Investigators

Abstract

This Major Research Instrumentation award provides funding for the development of triaxial vibrating sample magnetometry (VSM) to characterize anisotropic magnetic materials. A magnetometer is an instrument that allows one to characterize magnetic material, for example the magnets that stick to your refrigerator door. To fully characterize magnetic materials, it is necessary to measure all three components of the magnetic dipole moment vector. Triaxial VSMs however are not commercially available and less than a handful of research labs in Europe, Japan and Russia have attempted in the past to build a triaxial VSM. The instrument development allows for triaxial measurements to be done over a large temperature and field range. The vector coil sets that will be developed is extremely important for understanding the magnetic properties of anisotropic materials that have magnetic properties that vary with field direction. The new tools are expected to strengthen existing research and lead to new collaborations among academia and industry and will bring full vector magnetometry and torque capabilities to the Americas. Concrete plans are being developed to integrate the new tool in several graduate courses in Physics, MSEC, and Manufacturing Engineering each year and use the instrument for high school outreach activities and apprentice summer research programs in the College of Science and Engineering. The instrumentation development will be done by a graduate and undergraduate student. It is expected that the impact is much larger though once the tool is realized and tested with multiple graduate projects at Texas State and elsewhere benefiting from this unique capability. This instrument development award is to develop triaxial vibrating sample magnetometry (VSM) to measure all three components of the sample’s magnetic dipole moment simultaneously and allow for vector torque magnetometry as a function of temperature. Rather than designing a completely new instrument, the researcher will design and realize triaxial coil sets for two existing VSMs. The approach allows for a short runway, increases the adoptability of the new measurement tool benefitting from the existing user pool for both tools, and results in a large measurement parameter window (0-9 tesla, 2.8-1000 K). The method will be useful for the characterization of a wide range of materials. The project will directly enhance the research in 5 different academic programs (Physics, Chemistry, Manufacturing Engineering, Electrical Engineering, and MSEC). The realized vector torque magnetometer will enable researchers to study materials that have a complex magnetic anisotropy energy surface with multiple anisotropies originating from shape, strain, surface, step, flow, and a magnetic field applied during deposition. Such materials cannot be easily studied with a conventional torque magnetometer. Materials to be studied include oblique co-deposited NiFe films to be used in novel sensors and actuators, strained Fe doped epitaxial (InGa)2O3 films on anisotropic vicinal substrates, Nickel-Iron hydroxides and oxides that are currently being explored as electrode materials in lithium free batteries, and magnetic composites deposited by Magnetic Field Assisted Additive Manufacturing (MFAAM). MFAAM materials that are deposited by 2D (inkjet) or 3D (Fused Filament Fabrication) printing magnetic nanocomposites under applied magnetic field appear to have enhanced properties including a higher remanence, a larger susceptibility, and/or a stronger magnetic anisotropy. The coil sets and methods developed will be disseminated via the project’s website and peer-reviewed publications to allow other research groups to implement triaxial capability for their VSM. This award reflects NSF's statutory mission and has been deemed worthy of support through evaluation using the Foundation's intellectual merit and broader impacts review criteria.