7 research outputs found
Mechanisms of nonlinear spin-wave emission from a microwave driven nanocontact
We present a micromagnetic study of linear and nonlinear spin-wave modes
excited in an extended permalloy thin film by a microwave driven nanocontact.
We show that the linear mode having the frequency equal to the excitation
frequency (f) is driven by the ac Oersted field component perpendicular to the
static external field (applied in-plane of the sample). The nonlinear mode with
the frequency f /2 is excited as an independent eigenmode within a parametric
longitudinal pumping process (due ac Oersted field component parallel to the
bias field). Spectral positions of those modes are determined both in the space
and phase domain. The results are important for the transfer of information
coded into spin-waves between nanocontacts, and for synchronization of spin
transfer torque nano-oscillators.Comment: 5 pages, 4 figure
Magnetic domain-wall motion by propagating spin waves
We found by micromagnetic simulations that the motion of a transverse wall
(TW) type domain wall in magnetic thin-film nanostripes can be manipulated via
interaction with spin waves (SWs) propagating through the TW. The velocity of
the TW motion can be controlled by changes of the frequency and amplitude of
the propagating SWs. Moreover, the TW motion is efficiently driven by specific
SW frequencies that coincide with the resonant frequencies of the local modes
existing inside the TW structure. The use of propagating SWs, whose frequencies
are tuned to those of the intrinsic TW modes, is an alternative approach for
controlling TW motion in nanostripes
A spin-wave frequency doubler by domain wall oscillation
We present a new mechanism for spin-wave excitation using a pinned domain
wall which is forced to oscillate at its eigenfrequency and radiates spin
waves. The domain wall acts as a frequency doubler, as the excited spin waves
have twice the frequency of the domain wall oscillation. The investigations
have been carried out using micromagnetic simulations and enable the
determination of the main characteristics of the excited spin-waves such as
frequency, wavelength, and velocity. This behavior is understood by the
oscillation in the perpendicular magnetization which shows two anti-nodes
oscillating out of phase with respect to each other.Comment: 8 pages, 3 figure