Yang Xiaoping, Su Haibin
Institute of Advanced Studies, Nanyang Technological University, 50 Nanyang Avenue, 639798 Singapore.
Sci Rep. 2015 Oct 30;5:15849. doi: 10.1038/srep15849.
We present the formation of cupratelike electronic structures in KAgF3-related superlattices resulted from the confinement together with structural chemical modification by using the generalized gradient approximation augmented with maximally localized Wannier functions analysis. Strong antiferromagnetic coupling found in bulk KAgF3 is held in purely-fluoride KZnF3/KAgF3. Under 4% in-plane compression strain, its Fermi surface shape breaks away from the edge of electron pocket and resembles that of La2CuO4. While within half-fluoride SrTiO3/KAgF3, out-of-plane electronic reconstruction results in electron doping of AgF2 plane and antiferromagnetic state instability, and the Fermi surface shape presents considerable similarity to that in HgBaCuO4. These results shed light on two dimensional antiferromagnetic precursors of a new Ag(II) family of high-temperature superconductors.
我们展示了在与KAgF₃相关的超晶格中，通过使用广义梯度近似并结合最大局域化Wannier函数分析，由限制和结构化学修饰导致的类铜电子结构的形成。在块状KAgF₃中发现的强反铁磁耦合在纯氟化物KZnF₃/KAgF₃中得以保持。在4%的面内压缩应变下，其费米面形状偏离电子口袋边缘，类似于La₂CuO₄的费米面形状。而在半氟化物SrTiO₃/KAgF₃中，面外电子重构导致AgF₂平面的电子掺杂和反铁磁态不稳定，并且费米面形状与HgBaCuO₄中的费米面形状有相当大的相似性。这些结果为新型Ag(II)族高温超导体的二维反铁磁前驱体提供了线索。
