A New Fermionic State Revealed

Visual of fermi surface and new arc.
Fermi surface in paramagnetic and antiferromagnetic states (top), Emergence of surface states forming Fermi arcs  and their unusual splitting upon cooling below TN=24.5K (bottom).
Scientific Achievement

A new type of Fermi arcs have been discovered, with spin textures and novel magnetic splitting driven by long range antiferromagnetic order in cubic NdBi  not readily explained by existing theories.

Significance and Impact

This new class of material, where spin textured Fermi arcs are linked to an AFM order parameter, can be controlled by the application of ultrafast laser pulses, opening new avenues for terahertz spintronics.

Research details
  • ARPES revealed new surface states emerge when sample is cooled below AFM transition temperature in cubic NdBi.
  • These states split into hole- and electron-like bands that form Fermi arcs with opposing spin textures.

Benjamin Schrunk, Yevhen Kushnirenko, Brinda Kuthanazhi, Junyeong Ahn,  Lin-Lin Wang, Evan O’Leary, Kyungchan Lee, Andrew Eaton, Alexander Fedorov, Rui Lou, Vladimir Voroshnin, Oliver J. Clark, Jaime S´anchez-Barriga, Sergey L. Bud’ko, Robert-Jan Slager, Paul C. Canfield and Adam Kaminski, "Emergence of Fermi arcs due to magnetic splitting in an antiferromagnet," NATURE 603, 610-615 (2022).