Cava Lab finds new 2D insulator with ferromagnetic properties

By Laura Millsaps, Ames Laboratory Communications
Thursday, May. 9, 2019

Collaborating scientists at the U.S. Department of Energy’s Ames Laboratory, Brookhaven National Laboratory, and Princeton University have discovered a new layered ferromagnetic semiconductor, a rare type of material that holds great promise for next-generation electronic technologies.

Magneto-optical visualization of magnetic domains
Photo courtesy of Ames Laboratory

As the name implies, semiconductors are the Goldilocks of electrically conductive materials-- not a metal, and not an insulator, but a “just-right” in-between whose conducting properties can be altered and customized in ways that create the basis for the world’s modern electronic capabilities. Especially rare are the ones closer to an insulator than to a metal.

Princeton-based authors (l-r) Tai Kong, Robert J. Cava, Shu Guo and Danrui Ni
Photo by C. Todd Reichart

The recent discovery of ferromagnetism in semiconducting materials has been limited to a handful of mostly chromium-based compounds. But at the Ames Laboratory, researchers discovered ferromagnetism in a vanadium-iodine semiconductor, a material which has long been known but ignored; and which scientist Tai Kong compared to finding a “hidden treasure in our own backyard.” Now a postdoctoral researcher in the lab of Robert J. Cava, the Russell Wellman Moore Professor of Chemistry at Princeton University, Kong completed PhD research at the Ames Laboratory under supervision of Paul C. Canfield. And when the new material showed that it could have ferromagnetic response, Kong turned to Ames Laboratory for the magneto-optical visualization of magnetic domains that serves as the definitive proof of ferromagnetism. ...

Posted above is an excerpt of the full story. Read the full story here:
https://www.ameslab.gov/news/news-releases/2d-insulators-ferromagnetic-properties-are-rare-researchers-just-identified-new