[20p-D61-1~14] 10.1 Emerging materials in spintronics and magnetics (including fabrication and characterization methodologies)

2:30 PM - 2:45 PM JST(5:30 AM - 5:45 AM UTC)English Presentation

[20p-D61-6] X-ray helicity-dependent ultrafast demagnetization in a Pt/Co/Pt multilayer

〇Kihiro Yamada¹, Rei Kobayashi², Itaru Sugiura³, Yuya Kubota^4,5, Aoi Gocho⁶, Yusuke Akiyama², Kaiki Takemura², Sota Sasakura⁶, Keisuke Kaneshima⁶, Takuo Ohkouchi^4,6, Iwao Matsuda⁷, Teruo Ono³, Tadashi Togashi^4,5, Yoshihito Tanaka⁶, Motohiro Suzuki² (1.Tokyo Tech, 2.Kuwansei Univ., 3.ICR, Kyoto Univ., 4.JASRI, 5.RIKEN, 6.Hyogo Univ., 7.U Tokyo)

Keywords:

X-ray free electron laser,Ultrafast spectroscopy,Ultrafast demagnetization

When a femtosecond optical pulse irradiates a ferromagnetic metal, the magnetization dramatically
decreases on a sub-picosecond time scale. This phenomenon, known as ultrafast demagnetization, results from optically pumping electrons in the outer-most electron shell, in the visible to near-infrared (NIR) spectral ranges. On the other hand, the advent of x-ray free electron lasers has provided new possibilities for studying ultrafast demagnetization induced by the resonance excitation of core-to-valence electric dipole transitions [1]. We are currently exploring new ultrafast magnetic phenomena triggered by intense hard x-ray pulses using the SACLA facility. Here, we would like to present ultrafast demagnetization induced by circularly polarized hard x-ray pulses in a Pt/Co/Pt multilayer.