Argonne National Laboratory

Article | Materials Science

A tabletop phase-sensitive spin-torque magnetometry
In a study published in Physical Review Applied, researchers offer a route toward future advanced characterizations of spin-torque oscillators, magnonic circuits and tunneling junctions.
Left: Introduction of the phase shifter to the electrical path. Right: Evolution of ϕO measured on a Pt(6 nm)/Py(6 nm) device at different phase tuning ranges η and frequencies ω.
Left: Introduction of the phase shifter to the electrical path. Right: Evolution of ϕO measured on a Pt(6 nm)/Py(6 nm) device at different phase tuning ranges η and frequencies ω. The dashed lines are linear fits to the data.

Scientific Achievement

We have achieved optical detection of the spin-precession phase in ferromagnetic resonance, which can be used to determine the spin-orbit torque from heavy metals.

Significance and Impact

This technique allows both spatial- and phase-resolved detection of magnetization dynamics with tabletop optical measurements, which enables the characterization of local spin-orbit coupling in quantum materials and complex circuits for coherent spin-information processing.

Research Details

  • A heterodyne detection of the magneto-optical Kerr signal is used for measuring spin-torque driven ferromagnetic resonance.
  • Phase and spatial resolutions are demonstrated.
  • Extraction of phase delays induced by spin-orbit torque from different heavy metals. Results confirmed by simultaneous electrical detections.

Work was performed in part at the Center for Nanoscale Materials.

DOI: 10.1103/PhysRevApplied.11.034047

Download this highlight

About Argonne’s Center for Nanoscale Materials
The Center for Nanoscale Materials is one of the five DOE Nanoscale Science Research Centers, premier national user facilities for interdisciplinary research at the nanoscale supported by the DOE Office of Science. Together the NSRCs comprise a suite of complementary facilities that provide researchers with state-of-the-art capabilities to fabricate, process, characterize and model nanoscale materials, and constitute the largest infrastructure investment of the National Nanotechnology Initiative. The NSRCs are located at DOE’s Argonne, Brookhaven, Lawrence Berkeley, Oak Ridge, Sandia and Los Alamos National Laboratories. For more information about the DOE NSRCs, please visit https://​sci​ence​.osti​.gov/​U​s​e​r​-​F​a​c​i​l​i​t​i​e​s​/​U​s​e​r​-​F​a​c​i​l​i​t​i​e​s​-​a​t​-​a​-​G​lance.

Argonne National Laboratory seeks solutions to pressing national problems in science and technology. The nation’s first national laboratory, Argonne conducts leading-edge basic and applied scientific research in virtually every scientific discipline. Argonne researchers work closely with researchers from hundreds of companies, universities, and federal, state and municipal agencies to help them solve their specific problems, advance America’s scientific leadership and prepare the nation for a better future. With employees from more than 60 nations, Argonne is managed by UChicago Argonne, LLC for the U.S. Department of Energy’s Office of Science.

The U.S. Department of Energy’s Office of Science is the single largest supporter of basic research in the physical sciences in the United States and is working to address some of the most pressing challenges of our time. For more information, visit https://​ener​gy​.gov/​s​c​ience.