20 July 2016

MIT research group publishes unique topological results

New research published this week in Nature Physics explores a material that could play a key role in realizing spin-based electronics.

20july2016 mit topological(Left) Single crystal of gadolinium, platinum and bismuth [GdPtBi] made with naturally occurring elements. (Right) Single crystal of GdPtBi made with isotopically enriched 160Gd for neutron scattering experiments. Both crystals are approximately 1 mm in size. Images courtesy of the researchers.Topological insulators are materials with a unique quantum mechanical state that conduct electrons on the surface, but not within the interior/bulk. These materials have intrigued scientists for years, but are limited in their application because they lack the magnetic properties key to making next-generation electronics work.

New research published this week in Nature Physics demonstrates topological properties combined with intrinsic magnetism in a unique new compound, GdPtBi (gadolinium, platinum and bismuth), findings that could pave a path to spin-based electronics (or spintronics).

The MIT-based research team conducted experiments at the MagLab's DC Field Facility in high magnetic fields of over 30 tesla in order to map the electrical and magnetic properties of the material. They observed a magnetic transition at 25 T that had not been seen before, confirming the dual properties of magnetism and topological behavior in GdPtBi.

"This exciting work from a long-time MagLab user demonstrates the value of national user facilities in completing the experimental puzzle that begins in a scientist’s laboratory," said Tim Murphy, Director of the MagLab's DC Field Facility. "By conducting unique experiments at both the NIST Center for Neutron Research and the MagLab, this MIT research team provided an experimental framework to develop new and improved theoretical models that could continue to inspire new research for years to come."

The experimental efforts were led by research scientist Takehito Suzuki and included physics graduate student Aravind Devarakonda and physics undergraduate Yu-Ting Liu, a team of researchers based in the group of Joseph G. Checkelsky, assistant professor of physics at MIT.

Read more from MIT.

Last modified on 6 October 2016