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DOE OSTI · 1767007

Dynamic Nuclear Spin Polarization Induced by the Edelstein Effect at Bi(111) Surfaces

Jiang, Zijian·Soghomonian, V.·Heremans, J. J.
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Abstract

Nuclear spin polarization induced by hyperfine interaction and mainly 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 nonequilibrium carrier spin polarization by mainly the Edelstein effect at the Bi(111) surface, which then induces dynamic nuclear polarization by hyperfine interaction. Here, 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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75 CONDENSED MATTER PHYSICS, SUPERCONDUCTIVITY AND SUPERFLUIDITYSpin polarizationquantum interferencequantum interference effectsquantum transportsemimetals

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Jiang, Zijian, Soghomonian, V., Heremans, J. J.. 2020-09-03. Dynamic Nuclear Spin Polarization Induced by the Edelstein Effect at Bi(111) Surfaces. https://doi.org/10.1103/physrevlett.125.106802

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