Spin-transfer switching in full-Heusler Co_ 2FeAl-based magnetic tunnel junctions

摘要

We demonstrated spin-transfer magnetization switching using magnetic tunnel junctions (MTJs) with a full-Heusler alloy Co_2FeAl (CFA). We prepared CFA (1.5 nm)/MgO/CoFe (4 nm) ("CFA-free") and CFA (30 nm)/MgO/CoFeB (2 nm) ("CFA-reference") MTJs on a Cr(001) layer. The intrinsic critical current density (J_(c0)) of the CFA-free (CFA-reference) MTJ was 29 MA/cm~2 (7.1 MA/cm~2). The larger J_(c0) of the CFA-free MTJ is attributed to the significant enhancement of the Gilbert damping factor (～0.04) of the CFA due to the Cr layer. The J_(c0) of the CFA-reference is as small as that reported for typical CoFeB/MgO/CoFeB MTJs.