Abstract
In this paper, we detect the coupled oscillation of magnetic vortices in Ni81Fe19 gourd-shaped thin films electrically to evaluate the nonadiabatic spin-transfer torque (STT) coefficient β, which is important for understanding a variety of STT-related phenomena. We excite a translational mode in coupled magnetic vortices by applying an alternating electrical current that causes both STT and Oersted field torque. Since the coupled oscillation modes due to the STT and Oersted field torque have totally different eigenfrequencies, the coupled oscillation spectrum can be used to evaluate β, which is generally difficult to distinguish from the Oersted field contributions. Based on the ratio between the amplitudes of the spectrum's Lorentzian and anti-Lorentzian components, the value of β is found to be 0.085±0.016, which is 4.3 times larger than the Gilbert damping constant α.
| Original language | English |
|---|---|
| Article number | 064421 |
| Journal | Physical Review B |
| Volume | 98 |
| Issue number | 6 |
| DOIs | |
| Publication status | Published - 2018 Aug 23 |
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ASJC Scopus subject areas
- Electronic, Optical and Magnetic Materials
- Condensed Matter Physics
Cite this
Evaluating the nonadiabatic spin-transfer torque using coupled oscillation of magnetic vortices. / Horaguchi, Taisuke; Tanazawa, Tomoki; Nozaki, Yukio.
In: Physical Review B, Vol. 98, No. 6, 064421, 23.08.2018.Research output: Contribution to journal › Article
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TY - JOUR
T1 - Evaluating the nonadiabatic spin-transfer torque using coupled oscillation of magnetic vortices
AU - Horaguchi, Taisuke
AU - Tanazawa, Tomoki
AU - Nozaki, Yukio
PY - 2018/8/23
Y1 - 2018/8/23
N2 - In this paper, we detect the coupled oscillation of magnetic vortices in Ni81Fe19 gourd-shaped thin films electrically to evaluate the nonadiabatic spin-transfer torque (STT) coefficient β, which is important for understanding a variety of STT-related phenomena. We excite a translational mode in coupled magnetic vortices by applying an alternating electrical current that causes both STT and Oersted field torque. Since the coupled oscillation modes due to the STT and Oersted field torque have totally different eigenfrequencies, the coupled oscillation spectrum can be used to evaluate β, which is generally difficult to distinguish from the Oersted field contributions. Based on the ratio between the amplitudes of the spectrum's Lorentzian and anti-Lorentzian components, the value of β is found to be 0.085±0.016, which is 4.3 times larger than the Gilbert damping constant α.
AB - In this paper, we detect the coupled oscillation of magnetic vortices in Ni81Fe19 gourd-shaped thin films electrically to evaluate the nonadiabatic spin-transfer torque (STT) coefficient β, which is important for understanding a variety of STT-related phenomena. We excite a translational mode in coupled magnetic vortices by applying an alternating electrical current that causes both STT and Oersted field torque. Since the coupled oscillation modes due to the STT and Oersted field torque have totally different eigenfrequencies, the coupled oscillation spectrum can be used to evaluate β, which is generally difficult to distinguish from the Oersted field contributions. Based on the ratio between the amplitudes of the spectrum's Lorentzian and anti-Lorentzian components, the value of β is found to be 0.085±0.016, which is 4.3 times larger than the Gilbert damping constant α.
UR - http://www.scopus.com/inward/record.url?scp=85052805432&partnerID=8YFLogxK
UR - http://www.scopus.com/inward/citedby.url?scp=85052805432&partnerID=8YFLogxK
U2 - 10.1103/PhysRevB.98.064421
DO - 10.1103/PhysRevB.98.064421
M3 - Article
AN - SCOPUS:85052805432
VL - 98
JO - Physical Review B-Condensed Matter
JF - Physical Review B-Condensed Matter
SN - 2469-9950
IS - 6
M1 - 064421
ER -