2024-03-28T16:45:07Zhttps://eprints.lib.hokudai.ac.jp/dspace-oai/requestoai:eprints.lib.hokudai.ac.jp:2115/467682022-11-17T02:08:08Zhdl_2115_20053hdl_2115_145Suppression of in-plane tunneling anisotropic magnetoresistance effect in Co2MnSi/MgO/n-GaAs and CoFe/MgO/n-GaAs junctions by inserting a MgO barrierAkiho, TakafumiUemura, TetsuyaHarada, MasanobuMatsuda, Ken-ichiYamamoto, Masafumiopen accessCopyright 2011 American Institute of Physics. This article may be downloaded for personal use only. Any other use requires prior permission of the author and the American Institute of Physics. The following article appeared in Appl. Phys. Lett. 98, 232109 (2011) and may be found at https://dx.doi.org/10.1063/1.3595311cobalt alloyscobalt compoundsFermi levelgallium arsenideIII-V semiconductorsiron alloysmagnesium compoundsmanganese compoundsSchottky barriersspin valvestunnelling magnetoresistance427The effects of MgO tunnel barriers on both junction resistance and tunneling anisotropic magnetoresistance (TAMR) characteristics of Co2MnSi(CMS)/MgO/n-GaAs junctions and Co50Fe50(CoFe)/MgO/n-GaAs junctions were investigated. The resistance-area (RA) product of the CMS/MgO/n-GaAs junctions showed an exponential dependence on MgO thickness (t_[MgO]), indicating that the MgO layer acts as a tunneling barrier. The RA product of CMS/MgO/n-GaAs with t_[MgO] < 1 nm was smaller than that of the sample without MgO. The observed spin-valvelike magnetoresistance of CMS/n-GaAs and CoFe/n-GaAs Schottky tunnel junctions attributed to the TAMR effect did not appear in the cases of CMS/MgO/n-GaAs and CoFe/MgO/n-GaAs tunnel junctions. The lowering of the RA product and the suppression of the TAMR effect caused by inserting a thin MgO layer between CMS and n-GaAs were both possibly due to suppression of the Fermi-level pinning of GaAs and lowering of the Schottky barrier height.American Institute of Physics2011-06-06engjournal articleVoRhttp://hdl.handle.net/2115/46768https://doi.org/10.1063/1.35953110003-6951Applied Physics Letters9823232109https://eprints.lib.hokudai.ac.jp/dspace/bitstream/2115/46768/1/APL98-23_232109.pdfapplication/pdf416.99 KB2011-06-06