Femtosecond laser excitation of multiple spin waves and composition dependence of Gilbert damping in full-Heusler Co2Fe1−xMnxAl films

Abstract

Spin-wave dynamics in 30 nm thick Co2Fe1−xMnxAl full-Heusler films is investigated using time-resolved magneto-optical polar Kerr spectroscopy under an external field perpendicular to films. Damon-Eshbach (DE) and the first-order perpendicular standing spin-wave (PSSW) modes are observed simultaneously in four samples with x = 0, 0.3, 0.7, and 1. The frequency of DE and PSSW modes does not apparently depend on composition x, but damping of DE mode significantly on x and reaches the minimum as x = 0.7. The efficient coherent excitation of DE spin wave exhibits the promising application of Co2Fe0.3Mn0.7Al films in magnonic devices.

Simultaneous laser excitation of backward volume and perpendicular standing spin waves in full-Heusler Co2FeAl0.5Si0.5 films

“…Considering its frequency values in the reasonable frequency range of the PSSW mode38, its dispersion is tried to fit with Eq. (3) plus a constraint of Eq.…”

“…Cobalt-based full-Heusler ferromagnetic alloy films have attracted much attention due to potential applications both for spintronic1 and magnonic234 devices, which can be attributed to their high Curie temperature, high spin polarization and low magnetic damping34567. For applications of magnonic or magnon spintronic devices, spin waves are expected to serve as information carriers to realize transmission and processing of information891011.…”

“…Therefore, lots of observations in different systems are still necessary to clarify the excited conditions and characteristics of different SWMs, and provide more experiences for the future applications and the building of powerful theoretical models. A number of investigations are trying to fill these gaps3467.…”

“…However, Cheng et al . studied the spin-wave dynamics in Co 2 FeMnAl films using TR-MOKE spectroscopy under an out-of-plane external field applied, and observed the Damon-Eshbach (DE) spin wave combined with the perpendicular standing spin wave (PSSW) modes3. In addition, Loong et al .…”

Ultrafast Magnetization Dynamics in Epitaxial Ni-Mn-Sn Heusler Alloy Film

“…The TR-MOKE technique is important to obtain information about frequency (f ) and relaxation time (τ ) from optically excited magnetization precession. This method was applied in investigation of a number of Heusler alloys [6,[8][9][10][11][12][13][14][15][16][17]. In this work we present the results of experimental studies of shape memory Ni 54.3 Mn 31.9 Sn 13.8 epitaxial Heusler * corresponding author; e-mail: a.bonda@uwb.edu.pl alloy film, carrying out the TR-MOKE measurements as a function of applied magnetic field and laser pulse power.…”