Interfacial perpendicular magnetic anisotropy and damping parameter in ultra thin Co2FeAl films

Abstract

B2-ordered Co2FeAl films were synthesized using an ion beam deposition tool. A high degree of chemical ordering ∼81.2% with a low damping parameter (α) less than 0.004 was obtained in a 50 nm thick film via rapid thermal annealing at 600 °C. The perpendicular magnetic anisotropy (PMA) was optimized in ultra thin Co2FeAl films annealed at 350 °C without an external magnetic field. The reduced thickness and annealing temperature to achieve PMA introduced extrinsic factors thus increasing α significantly. However, the observed damping of Co2FeAl films was still lower than that of Co60Fe20B20 films prepared at the same thickness and annealing temperature.

Perpendicular magnetic anisotropy in the Heusler alloy Co2TiSi/GaAs(001) hybrid structure

“…[16][17][18] Very recently, the interface-induced PMA was discovered in a Co-based FHA (Co 2 FeAl) in contact with a MgO oxide layer. 19,20 The proposed explanation for the PMA is similar to that of CoFeB or Fe/MgO systems for which interfacial anisotropy induced by hybridization of Fe-, Co-3d and O-2p orbitals causes the a Electronic email: dau@pdi-berlin. PMA.…”

Structural and magnetic properties of Cr-diluted CoFeB

“…Ferromagnetic resonance (FMR) spectra were acquired using a broadband coplanar waveguide field-swept setup with frequencies up to 50 GHz. The frequency dependence on the linewidth was used to estimate an effective damping parameter 12 .…”

“…In addition, ferromagnetic resonance measurements were performed on CoFeCrB films, showing a much lower damping parameter compared to the values reported in the previous literature 9 . 12 ) were co-sputtered with different power ratios. By varying the powers applied to the two targets, the Cr content can be systematically changed from 10% to 30 %, along with a reducing Fe content.…”

Magnetic Multilayer Structures for Spin Torque Nano Oscillator

“…It has been suggested that K S was the main contribution leading to the PMA at a Co 2 FeAl/MgO interface [72].…”

“…It was considered as a promising electrode for perpendicular MTJs because of the PMA at the Co 2 FeAl/MgO interfaces [72].…”