We measured the spin rectification effect and the inverse spin Hall effect in Nb-doped SrTiO${}_3$ by pumping the spins from the ferromagnetic thin films into SrTiO${}_3$. The spin injection is increased when the doping level is increased. However, the spin to charge conversion efficiency which is measured by the spin Hall angle decreases when Nb concentration is more than $\sim$0.02 wt%. We argued that it is because that the electrons contributed to the inverse spin Hall effect are from the $d-$orbitals of Nb instead of Ti beyond this concentration. Our work points to the importance of orbital occupations in the (inverse) spin Hall effect. We may explore controllable spin and charge interconversion in oxide spintronics.

我们测量了掺Nb的SrTiO中的自旋整流效应和逆自旋霍尔效应${}_3$ 通过将自磁性薄膜的自旋泵浦到SrTiO中${}_3$。当掺杂水平增加时，自旋注入增加。但是，当Nb浓度大于10％时，以自旋霍尔角测量的自旋至电荷转换效率降低。$〜$0.02重量％。我们认为这是因为造成逆自旋霍尔效应的电子来自于$d-$超过此浓度，Nb代替Ti的轨道。我们的工作指出了轨道占领在（逆）自旋霍尔效应中的重要性。我们可能会探索氧化物自旋电子学中可控的自旋和电荷互变。