Research

The spin-orbit interaction enables inter-conversion between charge and spin currents. Examples of such are the spin Hall effect and the interface Rashba-Edelstein effect. However, so far these effects are mostly observed in nonmagnetic materials. We are interested in the spin-orbit effects in magnetic materials, particularly with the spins transverse to the magnetization direction. The interplay between the spin-orbit interaction and magnetic ordering may give rise to spin-orbit effects with new symmetries. 

Participating students: Ryan

Relevant Publications:

(1) A. M. Humphries, T. Wang, E. R. J. Edwards, S. R. Allen, J. M. Shaw, H. T. Nembach, J. Q. Xiao, T. J. Silva, X. Fan, "Observation of Spin-Orbit Effects with Spin Rotation Symmetry", Nature Communications, 8, 911 (2017)

(2) W. S. Aljuaid, S. R. Allen, A. Davidson, X. Fan, "Free-Layer-Thickness-dependence of the Spin Galvanic Effect with Spin Rotation Symmetry", Applied Physics Letters, 113, 122401 (2018) 

(3) W. Wang, T. Wang, V.P. Amin, Y. Wang, A. radhakrishnan, A. Davidson, S.R. Allen, T. J. Silva, H. Ohldag, D. Balzar, B.L. Zink, P.M. Haney, J.Q. Xiao, D.G. Cahill, V.O. Lorenz, X. Fan, "Anomalous Spin-Orbit Torques in Magnetic Single-Layer Films ", Nature Nanotechnology, 14, 819-824 (2019)

(4) A. Davidson, V.P. Amin, W.S. Aljuaid, P.M. Haney, X. Fan, "Perspectives of Electrically generated spin currents in ferromagnetic materials", Physics Letters A, 126228 (2020)

(5) S.M. Bleser, R.W. Greening, M.J. Roos, L.A. Hernandez, X. Fan, B.L. Zink, "Negative spin Hall angle and large spin-charge conversion in thermally evaporated chromium thin films", Journal of Applied Physics 131, 113904 (2022)

The spin dynamics carries fundamental information of the magnetic materials and is a crucial characteristic for high frequency applications. We study the spin dynamics in different experimental settings, including the ferromagnetic resonance and spin pumping-inverse spin Hall effect. Our recent interest is to identify the rectification signal in the spin pumping-inverse spin Hall effect measurement. 

Participating students: 

We are interested in the development of new measurement techniques to study the spin-orbit effects and spin dynamics.

Participating students: Ryan

Relevant Publications:

(1) H. Celik, H. Kannan, T. Wang, A. R. Mellnik, X. Fan, X. Zhou, R. Barri, D. C. Ralph, M. F. Doty, V. O. Lorenz, J. Q. Xiao, "Vector-Resolved Magnetooptic Kerr Effect Measurements of Spin-Orbit Torque", IEEE Transactions on Magnetics, 55, 1-5 (2019)

(2) T. Wang, S. Lendinez, M.B. Jungfleisch, J. Kolodzey, J.Q. Xiao, X. Fan, "Detection of spin-orbit torque with spin rotation symmetry", Applied Physics Letters, 116, 012404 (2020) Editor's Pick 

(3) R. W. Greening and X. Fan, "Influence of nonuniform magnetization reorientation on spin-orbit torque measurements", arXiv: 2207.10349 (2022)