Collective magnetization dynamics in ferromagnetic (Ga,Mn)As mediated by photo-excited carriers

Abstract

We present a study of photo-excited magnetization dynamics in ferromagnetic (Ga,Mn)As films observed by time-resolved magneto-optical measurements. The magnetization precession triggered by linearly polarized optical pulses in the absence of an external field shows a strong dependence on photon frequency when the photo-excitation energy approaches the band-edge of (Ga,Mn)As. This can be understood in terms of magnetic anisotropy modulation by both laser heating of the sample and by hole-induced non-thermal paths. Our findings provide a means for identifying the transition of laser-triggered magnetization dynamics from thermal to non-thermal mechanisms, a result that is of importance for ultrafast optical spin manipulation in ferromagnetic materials via non-thermal paths.

arXiv comment11 pages, 9 figures

References in corpus (22)

• Hole-mediated ferromagnetism in tetrahedrally coordinated semiconductors
• Ferromagnetism in semiconductors and oxides: prospects from a ten years' perspective
• Theory of ferromagnetic (III,Mn)V semiconductors
• Experimental observation of the optical spin transfer torque
• Photo-induced precession of magnetization in ferromagnetic (Ga,Mn)As
• Ultrafast Enhancement of Ferromagnetism via Photoexcited Holes in GaMnAs
• Magneto crystalline anisotropies in (Ga,Mn)As: A systematic theoretical study and comparison with experiment
• Light-Induced Magnetic Precession in (Ga,Mn)As Slabs: Hybrid Standing-Wave Damon-Eshbach Modes
• Experimental observation of the optical spin-orbit torque
• Ferromagnetic resonance study of free hole contribution to magnetization and magnetic anisotropy in modulation-doped Ga${}_{1-x}$Mn${}_x$As/Ga${}_{1-y}$Al${}_y$As:Be
• Light-induced magnetization precession in GaMnAs
• Coherent Magnetization Precession in GaMnAs induced by Ultrafast Optical Excitation
• Systematic study of magnetic linear dichroism and birefringence in (Ga,Mn)As
• Suppression of electron spin relaxation in Mn-doped GaAs
• Femtosecond Coherent Control of Spin with Light in (Ga,Mn)As ferromagnets
• Magnetic anisotropy switching in (Ga,Mn)As with increasing hole concentration
• Direct measurement of the three dimensional magnetization vector trajectory in GaMnAs by a magneto-optical pump-and-probe method
• Coherent control of magnetization precession in ferromagnetic semiconductor (Ga,Mn)As
• Coherent manipulation of magnetization precession in ferromagnetic semiconductor (Ga,Mn)As with successive optical pumping
• Photoreflectance Study of the Fundamental Optical Properties of (Ga,Mn)As Epitaxial Films
• Manipulating Femtosecond Spin--Orbit Torques with Laser Pulse Sequences to Control Magnetic Memory States and Ringing
• High Precision Magnetic Linear Dichroism Measurements in (Ga,Mn)As

Cited by in corpus (1)

• Manipulating Femtosecond Spin--Orbit Torques with Laser Pulse Sequences to Control Magnetic Memory States and Ringing