Voltage induced perpendicular magnetic anisotropy variation in ultrathin Fe80Co20 layers

초록

It has been reported that a large change of perpendicular magnetic anisotropy (PMA) in Au/Fe/MgO/polyimide/ITO system [1]. The dependence of the magnetooptical Kerr hysteresis loop shape on a bias voltage indicated that PMA is varied with a bias voltage.We measured voltage induced PMA changes in MgO (001)/Cr(10)/Au(50)/Fe80Co20(tF)/MgO(5)/Polymide(1500)/ITO(100) junctions (thickness in nm) by employing Brillouin light scattering (BLS). The Fe80Co20 layer thickness, tF , was varied from 0 to 0.75 nm on a single substrate by a wedge shape deposition technique. The PMA variations of each tF were determined from the local BLS measurement. We found that the PMA was changed from 0.940 to 0.868 (0.945) (erg/cm2) for +200 V (-200 V) bias voltages for tF = 0.55 nm. Furthermore, the hysteresis of PMA were obtained as a function of bias voltage.