Title :
Photoinduced Spin Precession and Ultrafast Demagnetization in Co2FeAl Films With Crossover From In-Plane to Perpendicular Magnetic Easy Axis
Author :
Zhe Zhang ; Di Wu ; Zhongzhi Luan ; Haochen Yuan ; Zhongzhi Zhang ; Jianhua Zhao ; Haibin Zhao ; Liangyao Chen
Author_Institution :
Dept. of Opt. Sci. & Eng., Fudan Univ., Shanghai, China
fDate :
7/7/1905 12:00:00 AM
Abstract :
Laser-induced spin precession and ultrafast demagnetization were investigated in MgO-capped Co2FeAl (MO-CFA) films. Both the Gilbert damping parameter α and the demagnetization time τm monotonically increased with the increasing perpendicular magnetic anisotropy as CFA thickness x was reduced to 0.6 nm. The increase in α may be explained by a stronger spin-orbit coupling. The τm of an L21 Co2FeAl film is larger than that of thick MO-CFA, but smaller than that of MO-CFA with x ≤ 0.9 nm, indicating that the restored orbital angular momentum may have a stronger and opposite effect on τm compared to the reduced spin polarization in thin MO-CFA.
Keywords :
aluminium alloys; cobalt alloys; damping; demagnetisation; high-speed optical techniques; iron alloys; magnesium compounds; magnetic thin films; metallic thin films; perpendicular magnetic anisotropy; spin polarised transport; spin-orbit interactions; Gilbert damping parameter; MgO-Co2FeAl; MgO-capped thin films; demagnetization time; in-plane easy axis; laser-induced spin precession; orbital angular momentum; perpendicular magnetic anisotropy; perpendicular magnetic easy axis; photoinduced spin precession; spin polarization; spin-orbit coupling; ultrafast demagnetization; Damping; Demagnetization; Films; Magnetization; Magnetomechanical effects; Perpendicular magnetic anisotropy; Ultrafast optics; Magnetic anisotropy; Magnetic films; Magnetodynamics; Magnetooptic Kerr effect; magnetic anisotropy; magnetic films; magnetooptic Kerr effect;
Journal_Title :
Magnetics Letters, IEEE
DOI :
10.1109/LMAG.2015.2483578
