Journal of the Vacuum Society of Japan
Online ISSN : 1882-4749
Print ISSN : 1882-2398
ISSN-L : 1882-2398
55 巻 , 5 号
  • 柿崎 明人
    2012 年 55 巻 5 号 p. 209-214
    発行日: 2012年
    公開日: 2012/06/20
    ジャーナル フリー
      Spin-resolved photoemission (SRPES) experiments have attracted much attention to investigate not only the spin dependent electronic structures of magnetic thin films and surfaces, but also those of non-magnetic materials, e.g. Rashba spin-split surface electronic states and edge states of topological insulators, etc. To show the utilities of SRPES, we show spin-resolved photoemission spectra of Fe thin films grown on Rh(001) surface and Rashba spin-split surface electronic states of √ 3 × √ 3 BiAg/Si(111). We also present our newly developed SRPES spectrometer equipped with VLEED-type spin detector, which achieves 100 times larger efficiency than those of conventional ones.
  • 小山 知弘, 千葉 大地, 小野 輝男
    2012 年 55 巻 5 号 p. 215-219
    発行日: 2012年
    公開日: 2012/06/20
    ジャーナル フリー
      Understanding of the mechanism of current-induced magnetic domain wall (DW) motion is essential for practical use of this phenomenon. Recent experiment has revealed that in perpendicularly magnetized Co/Ni nano-wire the threshold current density for DW motion is determined by ‘intrinsic pinning’ and it is independent of the DW pinning strength. Besides, the velocity of DW motion has been shown to be independent of external magnetic fields. In this review, recent progress of the study on the current-induced DW motion is described.
  • 柳内 克昭, 平田 京, 石田 洋一
    2012 年 55 巻 5 号 p. 220-225
    発行日: 2012年
    公開日: 2012/06/20
    ジャーナル フリー
      With the increase in the recording density of hard disk drives, the narrower magnetic pole and read-sensor widths in writing and reading heads are required, and techniques used for the magnetic behavior analysis in a nanoscale area is essential. The observation of the in-plane domain structure of the writer pole for a perpendicular recording (PMR) head was performed by electron holography in order to elucidate the mechanism of the pole erasure originating from the instability of the magnetic domain state. The results revealed that the stability of the domain structure is strongly related to the domain wall trapping, and the pole erasure can be suppressed by realizing the stable domain structures. With respect to a current perpendicular to plane (CPP)-giant magneto-resistive (GMR) head, which has been promising candidates of a next-generation reading head element, the insertion of non-magnetic materials, such as Cu, between the ferromagnetic pinned and free layers is known to increase the MR ratio. For realizing the practical use of the CPP-GMR head, effects of the insertion of materials on the increase in the MR ratio were investigated by X-ray magnetic circular dichroism (XMCD). The results revealed that XMCD is a powerful technique to obtain information on electronic states and magnetic moments with the help of the theoretical electronic band calculation. The potential application of secondary cantilever resonance magnetic force microscopy and spin-polarized scanning electron microscope to the in-situ magnetic imaging of PMR heads will be also discussed.