Quantitative investigation of the inverse Rashba-Edelstein effect in Bi/Ag and Ag/Bi on YIG

The inverse Rashba-Edelstein effect (IREE) is a spin conversion mechanism that recently attracts attention in spintronics and condensed matter physics. In this letter, we report an investigation of the IREE in Bi/Ag by using ferrimagnetic insulator yttrium iron garnet. We prepared two types of samples with opposite directions of the Rashba field by changing a stacking order of Bi and Ag. An electric current generated by the IREE was observed from both stacks, and an efficiency of spin conversion—characterized by the IREE length—was estimated by taking into account a number of contributions left out in previous studies. This study provides a further insight into the IREE spin conversion mechanism: important step towards achieving efficient spin-charge conversion devices.