The Giant Inverse Spin Hall Effect in Semiconductor Alloy/Ferromagnetic Insulator (Ge_1-x Bi _x /YIG) Spin Heterojunction

Ann-type semiconductor Ge1-x Bi x (x = 11.6-22.7%)alloy film is, for the first time, regulated to grow into a GeBi/yttriumiron garnet (YIG) spin heterojunction with a ferromagnetic insulatorY(3)Fe(5)O(12) garnet film wafer; testsfound that regulating the Bi ions content and enhancing spin-orbittorque (SOT) of the spin heterojunction can control signal voltageamplitude, bandwidth, and waveform of the inverse spin Hall effect(ISHE). The Bi doping can not only change the electron concentrationof the GeBi semiconductor film and mixing conductance of the GeBi/YIGbilayer but also increase the SOT between GeBi film and YIG film,driving the domain superfast reversal and enhancing the ISHE. Moreover,part of the Bi doping affects the magnetic moments distribution ofthe spin heterojunction and ferromagnetic resonance absorption. Ourresearch shows the possibility that the Ge1-x Bi x /YIG (x = 11.6-22.7%)spin heterojunction is one of the best for spin wave devices in thefuture.