论文标题
无限层镍盐中的准两维超导性的证据
Evidence for quasi-two-dimensional superconductivity in infinite-layer nickelates
论文作者
论文摘要
在被认为是数十年来的有前途的对铜矿的有前途的类似物之后，最近在无限层镍中发现了超导性，为探索高温超导性的机制提供了新的机会。然而，与最近报道的镍甲酸盐中的单波段准两维超导相反，镍表现出多带电子结构和意外的各向同性超导性，这挑战了镍镍中的铜酸盐样图片。在这里，我们表明镍的超导性实际上是各向异性和Quasi-Two二维本质上的，就像在酸锅中一样。通过合成具有增强的结晶度和超导性的高质量灯笼镍膜（$ t_ {c}^{onset} $ = 18.8 k，$ t_ {c}^{零} $ = 16.5 k），强烈的各向异性磁磁管pordiors perivies已被观察到。通过存在与角度依赖的$ t_ {C} $的尖峰和Berezinskii-kosterlitz- $ t_ {c} $相近的berezinskii-kosterlitz-thouless Trussition的存在，进一步证实了准二维的性质。因此，我们的工作表明，无限层镍的准二维超导性，这意味着单个3 $ d_ {x^2-y^2} $ - 在这些化合物中可能保持有效。
After being expected as a promising analogue to cuprates for decades, superconductivity was recently discovered in infinite-layer nickelates, providing new opportunities to explore mechanisms of high-temperature superconductivity. However, in sharp contrast to the single-band quasi-two-dimensional superconductivity in cuprates, nickelates exhibit a multi-band electronic structure and an unexpected isotropic superconductivity as reported recently, which challenges the cuprate-like picture in nickelates. Here, we show the superconductivity in nickelates is actually anisotropic and quasi-two-dimensional in nature, as that in cuprates. By synthesizing high-quality lanthanide nickelate films with enhanced crystallinity and superconductivity ($T_{c}^{onset}$ = 18.8 K, $T_{c}^{zero}$ = 16.5 K), strong anisotropic magnetotransport behaviors have been observed. The quasi-two-dimensional nature is further confirmed by the existence of a cusp-like peak of the angle-dependent $T_{c}$, and a Berezinskii-Kosterlitz-Thouless transition near $T_{c}$. Our work thus suggests a quasi-two-dimensional superconductivity in infinite-layer nickelates, implying a single-3$d_{x^2-y^2}$-band cuprate-like picture may remain valid in these compounds.
