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arXiv · 1906.05408

Dynamic nuclear spin polarization induced by Edelstein effect at Bi(111) surfaces

Zijian Jiang·Victoria Soghomonian·Jean J. Heremans
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Abstract

Nuclear spin polarization induced by hyperfine interaction and the Edelstein effect due to strong spin-orbit interaction is investigated by quantum transport in Bi(111) thin film samples. The Bi(111) films are deposited on mica by van der Waals epitaxial growth. The Bi(111) films show micrometer-sized triangular islands with 0.39 nm step height, corresponding to the Bi(111) bilayer height. At low temperatures a high current density is applied to generate a non-equilibrium carrier spin polarization by the Edelstein effect at the Bi(111) surface, which then induces dynamic nuclear polarization by hyperfine interaction. Comparative quantum magnetotransport antilocalization measurements indicate a suppression of antilocalization by the in-plane Overhauser field from the nuclear polarization and allow a quantification of the Overhauser field. Hence nuclear polarization was both achieved and quantified by a purely electronic transport-based approach.

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Zijian Jiang, Victoria Soghomonian, Jean J. Heremans. 2019-06-12. Dynamic nuclear spin polarization induced by Edelstein effect at Bi(111) surfaces. https://doi.org/10.1103/physrevlett.125.106802

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