Picosecond inverse magnetostriction in galfenol thin films

• DOI: 10.1063/1.4816014
• Publication Date: 2013-07-18T22:56:51Z
• Authors: J. V. Jäger; A. V. Scherbakov; T. L. Linnik; D. R. Yakovlev; M. Wang; P. Wadley; V. Holy; S. A. Cavill; A. V. Akimov; A. W. Rushforth; M. Bayer
• Keywords: 02 engineering and technology; 0210 nano-technology

Coherent high-amplitude precession of the magnetization and spin waves with frequencies up to 40 GHz are generated by injecting picosecond compressive and shear acoustic pulses into nanometer-sized galfenol (Fe81Ga19) films. The magnetization modulation is due to the picosecond inverse magnetostrictive effect. The oscillations of the magnetization measured by magneto-optical Kerr rotation last for several nanoseconds, and the maximum modulation of the in-plane effective magnetic field is as high as 40 mT. These results in combination with a comprehensive theoretical analysis show that galfenol films possess excellent properties for ultrafast magnetization control based on the picosecond inverse magnetostrictive effect.