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arXiv · 2207.12414

Electron pairs bound by the spin-orbit interaction in 2D gated Rashba materials with two-band spectrum

Yasha Gindikin·Igor Rozhansky·Vladimir A. Sablikov
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Abstract

We show that the bound electron pairs (BEPs) emerge in two-dimensional gated Rashba materials owing to the interplay of the pair spin-orbit interaction, produced by the Coulomb fields of interacting electrons, and the peculiarities of the band structure giving rise to a negative reduced mass of the interacting electrons. Our consideration is based on the four-band Bernevig-Hughes-Zhang model with the Rashba spin-orbit interaction created by the charges on the gate. The binding energy of the BEP varies with the gate voltage in a wide range across the entire width of the two-particle energy gap. Although the spin-orbit interaction destroys the spin quantization, the BEPs have a magnetic moment, which is created mainly by the orbital motion of the electrons and tuned by the gate voltage.

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Yasha Gindikin, Igor Rozhansky, Vladimir A. Sablikov. 2022-07-25. Electron pairs bound by the spin-orbit interaction in 2D gated Rashba materials with two-band spectrum. https://doi.org/10.1016/j.physe.2022.115551

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