Ultrafast heating effect on transient magnetic properties of L1(0)-FePt thin films with perpendicular anisotropy

作者：Zhao Jiaqi; Cui Boyin; Zhang Zongzhi^*; Ma B; Jin Q Y

来源：Thin Solid Films, 2010, 518(10): 2830-2833.

DOI：10.1016/j.tsf.2010.01.010

• FePt
• Thin films
• Ultrafast magnetization dynamics
• Perpendicular anisotropy
• Magneto-optical Kerr effect

Laser-induced ultrafast magnetization dynamics and transient coercivity behavior in perpendicular magnetized L1(0)-FePt films are investigated using the time-resolved polar magneto-optical Kerr technique. The magnetization after photo-excitation shows a dramatic reduction on the picosecond time scale. In contrast, the coercivity shows a weak decrease, accompanied by a skewed Kerr loop shape for low and intermediate fluences. The results can be interpreted by the laser-induced non-uniform demagnetization due to the weakened coupling between FePt grains of different size and/or components. The remaining coercivity vanishes when the film is fully demagnetized at higher fluence. We claim that the remaining coercivity can be manipulated by employing appropriate laser energy and film thickness, which may be helpful for application in heat-assisted magnetic recording.

• 出版日期2010-3-1
• 单位复旦大学