Tetrataenite Domain Structures

Tetrataenite is a fascinating mineral found naturally only in meteorites that consists of alternating layers of iron and nickel atoms. This ordered structure gives tetrataenite an extremely large magnetocrystalline anisotropy and high coercivity, and in fact has been proposed as an alternative for rare-earth element magnets that often come with environmentally damaging mining practices. The only problem with making it in a lab is that it takes millions of years naturally, so speeding that up is no easy task. 

Due to its high coercivity, tetrataenite has also been touted as a high-quality paleomagnetic recorder. Over the past decade, it has been used to study the evolution of iron-bearing meteorite parent bodies via synchrotron data collected on the cloudy zone microstructure (see image). However, the more we learn about tetrataenite, the more complex we realize it is. Analyzing and interpreting the data from these microstructures is tough because the neighboring grains have strong interactions and previous studies assumed the grains were single domain (which is likely not the case, see my work here).  

My postdoctoral work is focusing on peering deeper into tetrataenite and this microstructure via new advances in synchrotron magnetic imaging. In particular, I am using a technique called ptychography that will allow us to determine the magnetization of individual tetrataenite grains at a resolution 10x better than ever done before. This work is help us understand how to interpret tetrataenite magnetization and figure out what this unique mineral can tell us about planetary evolution. Check back here for future updates!