Time-Domain Measurement of Current-Induced Spin Wave Dynamics

Abstract

The performance of spintronic devices critically depends on three material parameters, namely, the spin polarization in the current (P), the intrinsic Gilbert damping (α), and the coefficient of the nonadiabatic spin transfer torque (β). However, there has been no method to determine these crucial material parameters in a self-contained manner. Here we show that P, α, and β can be simultaneously determined by performing a single series of time-domain measurements of current-induced spin wave dynamics in a ferromagnetic film.

Attenuation of propagating spin wave induced by layered nanostructures

“…3 Since the YIG is not compatible with standard silicon integrated circuit (IC) technology, spin wave propagation in ICcompatible materials such as FeNi is of importance for the realization of integrated circuits. [4][5][6][7][8][9][10][11][12][13][14] The magnetostatic surface wave (MSSW) in the FeNi film is the promising mode due to its high propagation velocity and a non-reciprocal character, which was also observed a long time ago in YIG films. [3][4][5] As revealed in the previous letter, 6 the nonreciprocal emission can be utilized for an initial input, since the non-reciprocal parameter (j) is unchanged even if a spin wave propagates a long distance.…”

“…The detail geometry of ACPS and experimental method are the same as reported in the previous letters. 6,7 Spin wave wavevector k $ 0.5 lm À1 is determined by the ACPS geometry, which corresponds to the resonant frequency of approximately x=2p $ 3.6 GHz. The spin wave frequencies were not changed even if we changed the Pt content.…”

Effect of Temperature on Magnetic Solitons Induced by Spin-Transfer Torque

“…The experimental results shown in the following are done with a magnetic field applied perpendicular to the film plane. We note that the droplet states can be affected by Joule heating [7], especially the FL precession [27,28]. We, thus, obtain our data by always keeping the electrical current constant and sweeping the magnetic fields.…”

Recent Developments in Magnetic Measurements: from Technical Method to Physical Knowledge

“…One of the first accomplishments of the stroboscopic methods has been the direct observation of the magnetization relaxation according to the LLG dynamics [18]. By investigating in the frequency range were stroboscopic methods can be applied we observe dynamical effects similar to those we are familiar with in the quasi-static regime, such as domain wall motion or nucleation of domains, but we also encounter new phenomena that require new theoretical approaches, such as fast switching by magnetization precession [19] [20], spin waves (magnetostatic, exchange, ...) [21], (whose spectrum can be continuous, or discrete in structured samples [22]), interaction of spin waves with domain walls and/or with spin polarized currents [23].…”