Precession frequency and switching time of the magnetization vector in the spin-valve active layer with perpendicular anisotropy

We analyze the dependence of the current density and magnetic field switching on the magnetic parameters of the material of the ferromagnetic layers of the spin valve. Comparison of critical characteristics of the spin valve with longitudinal anisotropy of ferromagnetic layers fabricared of different materials showed that the promising materials for the fabrication of spin valve are cobalt, iron, their alloys, ferroborates of cobalt and alloys of cobalt with gadolinium. For these materials we produced and analyzed the bifurcation diagrams of equations describing the switching process of the spin valve. Based on the study of the dynamics of the magnetization vector we obtained the numerical evaluation of time switching.

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Layer selective determination of magnetization vector configurations in an epitaxial double spin valve structure: Si(001)/Cu/Co/Cu/FeNi/Cu/Co/Cu

Applied Physics Letters ◽

10.1063/1.1306395 ◽

2000 ◽

Vol 77 (6) ◽

pp. 892-894 ◽

Cited By ~ 8

Author(s):

B. C. Choi ◽

A. Samad ◽

C. A. F. Vaz ◽

J. A. C. Bland ◽

S. Langridge ◽

...

Keyword(s):

Spin Valve ◽

Magnetization Vector ◽

Selective Determination ◽

Double Spin ◽

Valve Structure

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Частота и быстродействие спинового вентиля с планарной анизотропией слоев

Физика твердого тела ◽

10.21883/ftt.2020.09.49754.29h ◽

2020 ◽

Vol 62 (9) ◽

pp. 1361

Author(s):

Ю.А. Юсипова

Keyword(s):

Spin Valve ◽

Practical Interest ◽

Magnetization Vector ◽

Magnetization Dynamics ◽

Operating Modes ◽

Read Head ◽

Ferromagnetic Layers ◽

Valve Structure ◽

Switching Characteristics ◽

Layered Spin

The dynamics of the magnetization vector in the free layer of a layered spin-valve structure was simulated. As materials for the free and fixed layers, six magnetically soft ferromagnets with longitudinal anisotropy were considered. The types of magnetization dynamics that are of practical interest for MRAM and HMDD (switching of the magnetization vector), STNO (stable precession of the magnetization vector), and the base element PSL (switching of the magnetization vector with two probable outcomes) were highlighted. The ranges of currents and fields corresponding to these operating modes of the spin valve were calculated. The numerical calculations of the switching time showed that, among the considered materials for the MRAM cell, the most suitable is Co80Gd20 alloy, while for the HMDD read head, it is Fe60Co20B20. As a result of the precession frequency calculations, it was concluded that the Fe60Co20B20 alloy is optimal for the STNO ferromagnetic layers. For the implementation of PSL, the best switching characteristics were demonstrated by the Co93Gd7 alloy.

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Ultrafast Magnetization Reversal Dynamics on A Micrometer-Scale Thin Film Element Studied by Time Domain Imaging

MRS Proceedings ◽

10.1557/proc-648-p4.9 ◽

2000 ◽

Vol 648 ◽

Author(s):

B.C. Choi ◽

G. Ballentine ◽

M. Belov ◽

W.K. Hiebert ◽

M.R. Freeman

Keyword(s):

Domain Wall ◽

Time Domain ◽

Magnetization Reversal ◽

Switching Time ◽

Magnetization Vector ◽

Domain Wall Motion ◽

Time Resolved ◽

Imaging Results ◽

Resonance Frequencies ◽

The Time Domain

AbstractPicosecond time scale magnetization reversal dynamics in a 15nm thick Ni80Fe20 microstructure (10μm×2μm) is studied using time-resolved scanning Kerr microscopy. The time domain images reveal a striking change in the magnetization reversal mode, associated with the dramatic reduction in switching time when the magnetization vector is pulsed by a longitudinal switching field while a steady transverse biasing field is applied to the sample. According to the time domain imaging results, the abrupt change of the switching time is due to the change in the magnetization reversal mode; i.e., the nucleation dominant reversal process is replaced by domain wall motion if transverse biasing field is applied. Furthermore, magnetization oscillations subsequent to reversal are observed at two distinct resonance frequencies, which sensitively depend on the biasing field strength. The high frequency resonance at f=2 GHz is caused by damped precession of the magnetization vector, whereas another mode at f≈0.8 GHz is observed to arise from domain wall oscillation.

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