Speaker
Dylan Grandmont
(Department of Physics, University of Alberta, Edmonton, Alberta, Canada T6G 2G7)
Description
Torque magnetometry using torsional resonators provides a highly sensitive platform for resolving magnetic signatures in single meso-scale elements. In the static case, sample magnetizations are biased using a DC field while an AC excitation is applied at a frequency equal to the mechanical resonance of the torsional device. The resulting torque is then measured using an interferometric technique. One challenge in probing dynamics is that the interferometric signal must be demodulated at this fixed mechanical resonance; however, early studies in spin mechanics have met this challenge and produced a technique for simultaneously acquiring static and dynamic magnetization in the audio-frequency regime [1]. This approach has since been extended by orders of magnitude (up to several hundred megahertz), where spin resonances and other dynamic phenomena have been observed [2].
Pushing this frequency limit further still requires innovative new demodulation techniques. Here we discuss current methodologies to probe a single yttrium iron garnet microdisk for pinned resonant modes, higher order spin waves, and the Einstein-de Haas effect up to frequencies of a few gigahertz.
[1] J. E. Losby *et al*., Solid State Communications, **198** (2014), 3-6.
[2] J. E. Losby *et al*., Manuscript in prep.
Primary author
Dylan Grandmont
(Department of Physics, University of Alberta, Edmonton, Alberta, Canada T6G 2G7)
Co-authors
Fani Sani Fatemeh
(Department of Physics, University of Alberta, Edmonton, Alberta, Canada T6G 2G7 and National Institute for Nanotechnology, Edmonton, Alberta , Canada T6G 2M9)
John Thibault
(Department of Physics, University of Alberta, Edmonton, Alberta, Canada T6G 2G7)
Joseph Losby
(Department of Physics, University of Alberta, Edmonton, Alberta, Canada T6G 2G7 and National Institute for Nanotechnology, Edmonton, Alberta , Canada T6G 2M9)
Mark Freeman
(Department of Physics, University of Alberta, Edmonton, Alberta, Canada T6G 2G7 and National Institute for Nanotechnology, Edmonton, Alberta , Canada T6G 2M9)
Miro Belov
(National Institute for Nanotechnology, Edmonton, Alberta , Canada T6G 2M9)
Tayyaba Firdous
(Department of Physics, University of Alberta, Edmonton, Alberta, Canada T6G 2G7 and National Institute for Nanotechnology, Edmonton, Alberta , Canada T6G 2M9)
