Dependence of spin-transfer switching characteristics in magnetic tunnel junctions with synthetic free layers on coupling strength

作者：Nishimura Masayuki^*; Oogane Mikihiko; Naganuma Hiroshi; Inami Nobuhito; Morita Tadashi; Ando Yasuo

来源：Journal of Applied Physics, 2012, 111(7): 07C905.

DOI：10.1063/1.3672240

Dependence of spin-transfer switching characteristics on the interlayer exchange coupling strength in the MTJs with synthetic free layers of Co90Fe10/Ru/Co40Fe40B20 with strong coupling strength was investigated. In the MTJ with the relatively weakly coupled synthetic ferrimagnetic free layer, larger thermal stability (Delta(0)) and lower intrinsic critical current density (J(c0)) than those of the MTJ with the single free layer were observed. Meanwhile, in the MTJs with the strongly coupled synthetic ferri- or ferromagnetic free layers, very large Delta(0) and high J(c0) were observed probably due to high effective magnetic energy barrier. It was found that the MTJ with the relatively weakly coupled synthetic ferrimagnetic free layer is suitable for the STTRAM application.

• 出版日期2012-4-1