论文标题
具有可逆超导二极管效应的铁电超导体的预测
Prediction of ferroelectric superconductors with reversible superconducting diode effect
论文作者
论文摘要
非中心对称超导体可以具有超导二极管效应，其中当时间反转对称性也被损坏时，相反方向的临界电流有所不同。从理论上讲，我们提出的具有共存的铁电和超导性的铁电超导体可以支持铁电可逆的超导二极管二极管效应。 Through first-principles calculation, we predict that monolayer CuNb$_2$Se$_4$ (i.e., bilayer NbSe$_2$ intercalated with Cu) is such a ferroelectric superconductor, where ferroelectricity controls the layer polarization as well as the sign of spin-orbit coupling induced spin splittings.由于临界电流的非偏置效应与自旋分离成正比，因此在铁电的电交换时，超导二极管效应是可逆的。虽然我们使用CUNB $ _2 $ SE $ _4 $作为模型系统，但预测效果可以出现在一类二维超导双向双层中，并带有层间滑动引起的铁电性。我们的工作为研究二维材料中超导性与铁电性之间的相互作用打开了大门。
A noncentrosymmetric superconductor can have a superconducting diode effect, where the critical current in opposite directions is different when time-reversal symmetry is also broken. We theoretically propose that a ferroelectric superconductor with coexisting ferroelectricity and superconductivity can support a ferroelectric reversible superconducting diode effect. Through first-principles calculation, we predict that monolayer CuNb$_2$Se$_4$ (i.e., bilayer NbSe$_2$ intercalated with Cu) is such a ferroelectric superconductor, where ferroelectricity controls the layer polarization as well as the sign of spin-orbit coupling induced spin splittings. Because the nonreciprocal effect of the critical current is proportional to the spin splittings, the superconducting diode effect is reversible upon electric switch of ferroelectricity. While we use CuNb$_2$Se$_4$ as a model system, the predicted effect can appear in a class of two-dimensional superconducting bilayers with ferroelectricity induced by interlayer sliding. Our work opens the door to studying the interplay between superconductivity and ferroelectricity in two-dimensional materials.
