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arXiv · 2008.06003

In situ tuning of symmetry-breaking induced non-reciprocity in giant-Rashba semiconductor BiTeBr

Mátyás Kocsis·Oleksandr Zheliuk·Péter Makk·Endre Tóvári·Péter Kun·Oleg Evgenevich Tereshchenko·Konstantin Aleksandrovich Kokh·Takashi Taniguchi·Kenji Watanabe·Justin Ye·Szabolcs Csonka
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Abstract

Non-reciprocal transport, where the left to right flowing current differs from the right to left flowing one, is an unexpected phenomenon in bulk crystals. BiTeBr is a non-centrosymmetric material, with a giant Rashba spin-orbit coupling which presents this unusual effect when placed in an in-plane magnetic field. It has been shown that this effect depends strongly on the carrier density, however, in-situ tuning has not yet been demonstrated. We developed a method where thin BiTeBr flakes are gate tuned via ionic-liquid gating through a thin protective hBN layer. Tuning the carrier density allows a more than \SI{400}{\percent} variation of the non-reciprocal response. Our study serves as a milestone on how a few-atomic-layer-thin van der Waals protection layer allows ionic gating of chemically sensitive, exotic nanocrystals.

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Mátyás Kocsis, Oleksandr Zheliuk, Péter Makk, Endre Tóvári, Péter Kun, Oleg Evgenevich Tereshchenko, Konstantin Aleksandrovich Kokh, Takashi Taniguchi, Kenji Watanabe, Justin Ye, Szabolcs Csonka. 2020-08-17. In situ tuning of symmetry-breaking induced non-reciprocity in giant-Rashba semiconductor BiTeBr. https://doi.org/10.1103/physrevresearch.3.033253

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