Gibbons, JonathanDohi, TakaakiAmin, Vivek P.Xue, FeiRen, HaowenXu, Jun-WenArava, HanuShim, SohoSaglam, HilalLiu, YuziPearson, John E.Mason, NadyaPetford-Long, Amanda K.Haney, Paul M.Stiles, Mark D.Fullerton, Eric E.Kent, Andrew D.Fukami, ShunsukeHoffman, Axel2023-12-082023-12-082022-08Gibbons, J., Dohi, T., Amin, V. P., Xue, F., Ren, H., Xu, J.-W., Arava, H., Shim, S., Saglam, H., Liu, Y., Pearson, J. E., Mason, N., Petford-Long, A. K., Haney, P. M., Stiles, M. D., Fullerton, E. E., Kent, A. D., Fukami, S., & Hoffmann, A. (2022). Large Exotic Spin Torques in Antiferromagnetic Iron Rhodium. Physical Review Applied, 18(2), 024075. https://doi.org/10.1103/PhysRevApplied.18.024075https://hdl.handle.net/1805/37306Spin 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 antiferromagnetic 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.en-USPublisher PolicySpin Hall effectSpin currentSpin torqueAntiferromagnetsFerromagnetic resonanceHall barResistivity measurementsArticle