Journal ArticleDOI
Inductive measurement of ultrafast magnetization dynamics in thin-film Permalloy
TLDR
In this article, an inductive technique for the measurement of dynamical magnetic processes in thin-film materials is described using 50 nm films of Permalloy (Ni81Fe19) and data are presented for impulse and step-response experiments with the applied field pulse oriented in the plane of the film and transverse to the anisotropy axis.Abstract:
An inductive technique for the measurement of dynamical magnetic processes in thin-film materials is described. The technique is demonstrated using 50 nm films of Permalloy (Ni81Fe19). Data are presented for impulse- and step-response experiments with the applied field pulse oriented in the plane of the film and transverse to the anisotropy axis. Rotation times as short as 200 ps and free oscillations of the magnetization after excitation are clearly observed. The oscillation frequency increases as the dc bias field parallel to the anisotropy axis increases as predicted by classical gyromagnetic theory. The data are fitted to the Landau–Lifshitz equation, and damping parameters are determined as a function of dc bias field. Damping for both impulse and step excitations exhibits a strong dependence on bias field. Damping for step excitations is characterized by an anomalous transient damping which rapidly increases at low dc bias field. Transformation of the data to the frequency domain reveals a higher order precessional mode which is also preferentially excited at low dc bias fields. A possible source for both phenomena is precessional mode saturation for large peak rotations. The technique has the potential for 20 ps resolution, although only 120 ps resolution is demonstrated due to the limited bandwidth of the waveguides used.read more
Citations
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Journal ArticleDOI
Influence of magnetic properties on magnetization dynamics of high-/spl rho/ films
Jeffrey McCord,J. Paul +1 more
TL;DR: In this paper, the influence of magnetic properties on the magnetization dynamics of high resistivity amorphous CoZrTa thin films was investigated and a strong correlation with magnetic coercivity was found.
Journal ArticleDOI
Intrinsic nonlinear ferromagnetic relaxation (invited)
A. Yu. Dobin,Randall H Victora +1 more
TL;DR: In this paper, the intrinsic damping mechanism arising from the magnon-magnon scattering is theoretically studied in three dimensional and two dimensional ferromagnets, and an analytic theory is developed to identify the three-maddening and four-addressing processes responsible for rapid relaxation.
Patent
Ultrafast magnetization reversal
TL;DR: In this article, a scheme for ultrafast magnetization reversal in an in-plane magnetized layer (3) is disclosed. But the scheme requires the external magnetic field Hex to be applied approximately perpendicular to the magnetization M.
Journal ArticleDOI
Microwave assisted resonant domain wall nucleation in permalloy nanowires
TL;DR: In this paper, a system was designed to study microwave assisted domain wall nucleation in permalloy nanowires and the authors found a substantial decrease in the nucleation field when microwave fields are applied, in comparison to pulse fields.
Journal ArticleDOI
Electrical detection of microwave assisted magnetization reversal by spin pumping
TL;DR: In this article, the authors investigated microwave assisted magnetization reversal in a bilayer system of Pt/ferromagnet by detecting a change in the polarity of the spin pumping signal.
References
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