Pure crossed Andreev reflection assisted transverse valley currents in $\alpha-\mathcal{T}_3$ lattices

W. Zeng; R. Shen

doi:10.1103/physrevb.106.094503

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arXiv · 2205.14930

Pure crossed Andreev reflection assisted transverse valley currents in $\alpha-\mathcal{T}_3$ lattices

W. Zeng·R. Shen

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Abstract

We propose a novel method for the generation of the transverse valley currents, which is based on the pure crossed Andreev reflection (pCAR) in the superconducting hybrid junctions composed of the gapped $\alpha-\mathcal{T}_3$ lattices with ferromagnet-induced exchange interaction. The angle-resolved pCAR probability is asymmetric for a given valley, resulting in the transverse valley currents with zero net charge. This pCAR assisted charge-valley conversion is highly efficient with the valley Hall angle reaching an order of unity, suggesting potential applications for valleytronic devices.

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W. Zeng, R. Shen. 2022-05-30. Pure crossed Andreev reflection assisted transverse valley currents in $\alpha-\mathcal{T}_3$ lattices. https://doi.org/10.1103/physrevb.106.094503

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