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arXiv · 1604.00751

Universal scaling for the spin-electricity conversion on surface states of topological insulators

K. T. Yamamoto·Y. Shiomi·Kouji Segawa·Yoichi Ando·E. Saitoh
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Abstract

We have investigated spin-electricity conversion on surface states of bulk-insulating topological insulator (TI) materials using a spin pumping technique. The sample structure is Ni-Fe|Cu|TI trilayers, in which magnetic proximity effects on the TI surfaces are negligibly small owing to the inserted Cu layer. Voltage signals produced by the spin-electricity conversion are clearly observed, and enhanced with decreasing temperature in line with the dominated surface transport at lower temperatures. The efficiency of the spin-electricity conversion is greater for TI samples with higher resistivity of bulk states and longer mean free path of surface states, consistent with the surface spin-electricity conversion.

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K. T. Yamamoto, Y. Shiomi, Kouji Segawa, Yoichi Ando, E. Saitoh. 2016-04-04. Universal scaling for the spin-electricity conversion on surface states of topological insulators. https://doi.org/10.1103/physrevb.94.024404

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