Details

Autor(en) / Beteiligte

• Yakata, S.
• Kubota, H.
• Suzuki, Y.
• Yakushiji, K.
• Fukushima, A.
• Yuasa, S.
• Ando, K.

Titel

Influence of perpendicular magnetic anisotropy on spin-transfer switching current in CoFeB∕MgO∕CoFeB magnetic tunnel junctions

Ist Teil von

• Journal of applied physics, 2009-04, Vol.105 (7)

Erscheinungsjahr

2009

Link zum Volltext

Quelle

Alma/SFX Local Collection

Beschreibungen/Notizen

• We investigated the spin-torque diode effect in submicron-scale Co60Fe20B20∕MgO∕(CoxFe1−x)80B20 (0⩽x⩽0.9) magnetic tunnel junctions (MTJs) under perpendicular magnetic fields Hext up to 10kOe. A single peak was clearly observed in every spin-torque diode spectrum and the dependence of resonant frequency fres on Hext was well explained by using Kittel’s formula. It was found that effective demagnetizing fields in the perpendicular-to-plane direction of the Fe-rich CoFeB free layers obtained from the spectra were considerably smaller than those expected from the magnetizations of the free layers. This suggested that the Fe-rich CoFeB free layers exhibited a perpendicular magnetic anisotropy, which agreed well with the reduced switching current density in the MTJs.