Magnetization Reversal of Magnetic Tunnel Junctions by Low-Current Pulses

The magnetization curves of highly resistive CoFeB/MgO/CoFeB/IrMn magnetic tunnel junctions (MTJs) are studied in dependence of the electrical field in the barrier. It is shown that the magnetoresistive hysteresis curve of the free layer (FL) is shifted by 6 Oe with the increase of the applied voltage from 50 mV to 1 V. The 100-ns voltage pulse of 2 V changes the magnetization of the FL by 50%. At that the current density of the pulse is small enough as
$10^{{3}}$
A/cm2. The most probable explanation of the observed effect is the dependence of the exchange interaction between the ferromagnetic (FM) layers in the MTJ on the electric field in the barrier, which reaches a value of
$10^{{7}}$
V/cm. The architecture of the MRAM cell operating on the observed effect is proposed.