Large exotic spin torques in antiferromagnetic iron rhodium.

Journal Article · 29 August 2022 · Physical Review Applied

DOI:https://doi.org/10.1103/PhysRevApplied.18.024075· OSTI ID:1902339

Gibbons, Jonathan; Dohi, Takaaki; Amin, Vivek P.; Xue, Fei; Ren, Haowen; Xu, Jun-Wen; Arava, Hanu; Shim, Soho; Saglam, Hilal; Liu, Yuzi; Pearson, John E.; Petford-Long, Amanda K.

Spin torque is a promising tool for driving magnetization dynamics for computing technologies. These torques can be easily produced by spin-orbit effects, but for most conventional spin source materials, a high degree of crystal symmetry limits the geometry of the spin torques produced. Magnetic ordering is one way to reduce the symmetry of a material and allow exotic torques, and antiferromagnets are particularly promising because they are robust against external fields. We present spin torque ferromagnetic resonance (ST-FMR) measurements and second harmonic Hall measurements characterizing the spin torques in anti -ferromagnetic iron rhodium alloy. We report extremely large, strongly temperature-dependent exotic spin torques with a geometry apparently defined by the magnetic ordering direction. We find the spin torque efficiency of iron rhodium to be (207 +/- 94)% at 170 K and (88 +/- 32)% at room temperature. We support our conclusions with theoretical calculations showing how the antiferromagnetic ordering in iron rhodium gives rise to such exotic torques.

• Research Organization: Argonne National Lab. (ANL), Argonne, IL (United States)
• Sponsoring Organization: National Science Foundation (NSF); USDOE Office of Science - Office of Basic Energy Sciences - Scientific User Facilities Division; USDOE Office of Science - Energy Frontier Research Center
• DOE Contract Number: AC02-06CH11357
• OSTI ID: 1902339
• Journal Information: Physical Review Applied, Vol. 18, Issue 2
• Country of Publication: United States
• Language: English