• 제목/요약/키워드: Induced magnetic anisotropy

검색결과 48건 처리시간 0.027초

Mumetal 박막의 성장온도가 유도자기이방성에 미치는 영향 (Effect of the Growing Temperature on the Induced Anisotropy of Mumetal Thin Film)

  • 이영우;김철기;김종오
    • 한국자기학회지
    • /
    • 제12권2호
    • /
    • pp.46-50
    • /
    • 2002
  • 110$\AA$ 두께의 Mumetal 박막을 자기장하에서 기판온도를 변화시키면서 제작하고, 고진공 분위기에서 자기장중 열처리를 수행하였다. 박막에 유도되는 자기이방성은 인가자기장 방향에서 30$^{\circ}$간격으로 180$^{\circ}$까지 자기이력곡선을 측정하여 조사하였다. 기판 온도가 증가할수록 용이축 방향의 보자력은 감소하였으나 일축이방성은 인가자기장 방향에서 벗어났다. 20$0^{\circ}C$에서 한 시간 동안 자기장중 열처리를 수행하면 기판온도에 상관없이 일축이방성이 향상되었다. 기판온도가 5$0^{\circ}C$ 이하일때 4.3 Oe의 이방성 자기장을 나타냈으며 기판온도가 증가할수록 이방성 자기장은 감소하였다. Mumetal 박막의 일축이방성은 열처리 전후 모두 5$0^{\circ}C$에서 가장 잘 유도되었다.

Effect of Magnetic Property Modification on Current-Induced Magnetization Switching with Perpendicular Magnetic Layers and Polarization-Enhancement Layers

  • Kim, Woo-Jin;Lee, Kyung-Jin;Lee, Taek-Dong
    • Journal of Magnetics
    • /
    • 제14권3호
    • /
    • pp.104-107
    • /
    • 2009
  • The effects of the magnetic property variation on current-induced magnetization switching in magnetic tunnel junction with perpendicular magnetic anistoropy (PMA) and the soft magnetic polarization-enhancement layers (PELs) inserted between the layers with PMA and the MgO layer was studied. A micromatnetic model was used to estimate the switching time of the free layer by different applied current densities, with changing saturation magnetization ($M_s$) of the PELs, interlayer exchange coupling between PMA layers and PELs. The switching time could be significantly reduced at low current densities, by increasing $M_s$ of PELs and decreasing interlayer exchange coupling.

전기전도도의 비균질성을 고려한 정밀 두뇌 모형 내부에서 유기되는 유도 전기장 분포해석 (Numerical Analysis of Electric Field Distribution Induced Inside a Realistic Brain Model Considering Conductivity Heterogeneity)

  • 김동훈;이일호;원철호
    • 전기학회논문지
    • /
    • 제57권2호
    • /
    • pp.314-319
    • /
    • 2008
  • In this paper, the electric field distribution induced inside the brain during Transcranial Magnetic Stimulation(TMS) has been thoroughly investigated in terms of tissue heterogeneity and anisotropy as well as different head models. To achieve this, first, an elaborate head model consisting of seven major parts of the head has been built based on the Magnetic Resonance(MR) image data. Then the Finite Element Method(FEM) has been used to evaluate the electric field distribution under different head models or three different conductivity conditions when the head model has been exposed to a time varying magnetic field achieved by utilizing the Figure-Of-Eight(FOE) stimulation coil. The results show that the magnitude as well as the distribution of the induced field is significantly affected by the degree of geometrical asymmetry of head models and conductivity conditions with respect to the center of the FOE coil.

Effect of NiO spin switching on the Fe film magnetic anisotropy in epitaxially grown Fe/NiO/Ag(001) and Fe/NiO/MgO(001) systems

  • 김원동;박주상;황찬용
    • 한국진공학회:학술대회논문집
    • /
    • 한국진공학회 2009년도 제38회 동계학술대회 초록집
    • /
    • pp.366-366
    • /
    • 2010
  • Single crystalline Fe/NiO bilayers were epitaxially grown on Ag(001) and on MgO(001), and investigated by Low Energy Electron Diffraction (LEED), Magneto-Optic Kerr Effect (MOKE), and X-ray Magnetic Linear Dichorism (XMLD). We find that while the Fe film has an in-plane magnetization in both Fe/NiO/Ag(001) and Fe/NiO/MgO(001) systems, the NiO spins switch from out-of-plane direction in Fe/NiO/MgO(001) to in-plane direction in Fe/NiO/Ag(001). These two different NiO spin orientations generate remarkable different effects that the NiO induced magnetic anisotropy in the Fe film is much greater in Fe/NiO/Ag(001) than in Fe/NiO/MgO(001). XMLD measurement shows that the much greater magnetic anisotropy in Fe/NiO/Ag(001) is due to a 90o-coupling between the in-plane NiO spins and the in-plane Fe spins which causes a switching of the NiO spins during the Fe magnetization reversal.

  • PDF