Efficient Edelstein Effects in One-Atom-layer Tl-Pb Compound

We have investigated direct and inverse Edelstein effects in a one-atom-layer Tl-Pb compound with a large Rashba-type spin splitting. In spin pumping experiments at room temperature, spin-to-charge conversion voltage due to the inverse Edelstein effect is clearly observed in Py/Cu/Tl-Pb trilayer samples. To confirm efficient spin-charge interconversion in Tl-Pb compounds, the direct Edelstein effect is also studied in the same trilayer samples by measuring the modulation of the effective magnetization damping in the Py layer via the charge-to-spin conversion in the Tl-Pb layer. Using the results of both direct and inverse Edelstein effects, the Edelstein length is estimated to be ∼0.1 nm for Tl-Pb compounds.