[23a-A205-1~13] 10.2 Fundamental and exploratory device technologies for spin

▼ [23a-A205-8] Magnetic damping in Cu₂Sb-type MnCrAlGe thin film investigated by all-optical pump-probe method

〇Yuta Sasaki¹, Ryoya Hiramatsu², Yohei Kota³, Takahide Kubota², Yoshiaki Sonobe¹, Akimasa Sakuma², Koki Takanashi^2,4, Shinya Kasai¹, Yukiko Takahashi¹ (1.NIMS, 2.Tohoku Univ., 3.NIT Fukushima Col., 4.JAEA)

Keywords:spintronics, Ferromagnetic thin film, all-optical method

A large perpendicular magnetic anisotropy(PMA), small saturation magnetization(M_s) and small magnetic damping constant α are strongly desired in few nano-meter thick ferromagnetic thin films for the future spintronic memory devices. Recently, perpendicularly magnetized (001)-textured Cu₂Sb-type MnCrAlGe ultrathin film was grown onto thermally oxidized Si substrates. The static magnetic properties, PMA energy of 0.7 MJ/m³ and M_s of 300 kA/m, are reported in previous studies, however, there is no report on α because the magnetization precession frequency in the large PMA materials reaches to terahertz(THz) frequency. Here, we investigated the sub-THz magnetization dynamics in MnCrAlGe ultrathin film using all-optical method which can be used up to several THz frequency.