13:30 〜 15:30
▲ [18p-PB1-28] Voltage-controlled magnetic anisotropy in ultrathin nickel
キーワード：Voltage-controlled magnetic anisotropy, X-ray magnetic circular dichroism, Nickel
Voltage-controlled magnetic anisotropy (VCMA) in 3d-transition metals has been intensively studied. Recently, it has been reported that a Co/MgO, where one electron is added to 3d-orbitals of Fe, shows larger VCMA (~80 fJ/Vm) than that of Fe/MgO(~30 fJ/Vm). In this study, we have characterized the VCMA effect and the voltage-induced changes of magnetic moments in a Ni/MgO, where one electron is added to 3d-orbitals of Co.
We fabricated magnetic tunnel junction devices with Fe(0.3 nm)/Ni(0.14 nm)/MgO(1.4 nm)/Fe(10 nm) multilayer, and analyzed the VCMA effect. For the characterization of magnetic moments of Ni, a tunnel junction with an Fe(0.3 nm)/Ni(0.14 nm)/MgO(2 nm)/SiO2(5 nm) was prepared. We measured X-ray absorption and its X-ray magnetic circular dichroism (XMCD) around Ni-L2,3 edges at BL25SU, SPring-8. We found that bias-voltage changes the XMCD spectra, which suggests that magnetic moments of Ni were modulated by the bias-voltage.
We fabricated magnetic tunnel junction devices with Fe(0.3 nm)/Ni(0.14 nm)/MgO(1.4 nm)/Fe(10 nm) multilayer, and analyzed the VCMA effect. For the characterization of magnetic moments of Ni, a tunnel junction with an Fe(0.3 nm)/Ni(0.14 nm)/MgO(2 nm)/SiO2(5 nm) was prepared. We measured X-ray absorption and its X-ray magnetic circular dichroism (XMCD) around Ni-L2,3 edges at BL25SU, SPring-8. We found that bias-voltage changes the XMCD spectra, which suggests that magnetic moments of Ni were modulated by the bias-voltage.