09:45 〜 10:00
▼ [11a-M101-4] Spin-charge conversion in highly oriented bismuth using spin-torque ferromagnetic resonance
キーワード:spintronics, inverse spin Hall effect, bismuth
In spintronics, bismuth (Bi) is one of the most remarkable materials due to its strong spin-orbit interaction, which induces spin-charge conversion; the spin Hall effect (SHE) and the inverse SHE (ISHE). Large spin conversion efficiency is expected in Bi. However, the spin Hall angle investigated in amorphous and polycrystalline Bi was much smaller than that of other materials with smaller spin-orbit interaction. It is significant to study spin-charge conversion in highly oriented Bi grown on single crystalline iron (Fe). To estimate spin conversion property of Bi, we introduced two different methods related to the ISHE and the SHE, respectively. In the former, spin current, generated under ferromagnetic resonance of the Fe, was injected into the Bi and converted to charge current due to the ISHE. Rf charge current transmitting in the Bi/Fe was converted to spin current due to the SHE of the Bi, which flew into the Fe and changed its anisotropic magnetoresistance. From change in resistance, spin Hall angle of our Bi was estimated to be 0.22 ± 0.03. Other physical parameters including spin diffusion length will be discussed in the presentation.