Using tight-binding models and first-principles calculations, we demonstrate the possibility to achieve a quantum anomalous Hall (QAH) phase on a two-dimensional square lattice, which can be realized in monolayers of double perovskites. We show that effective intersite spin-orbit coupling between eg orbitals can be induced perturbatively, giving rise to a QAH state. Moreover, the effective spin-orbit coupling can be enhanced by octahedral rotations. Based on first-principles calculations, we propose that this type of QAH state could be realized in La2MnIrO6 monolayers, with the size of the gap as large as 26 meV in the ideal case. We observe that the electronic structure is sensitive to structural distortions, and that an enhanced Hubbard U tends to stabilize the nontrivial gap.
Interplay of Intersite Charge Transfer, Antiferromagnetism, and Strain in Barocaloric ACu$_3$Fe$_4$O$_{12}$ Quadruple Perovskites
Centro de Investigación en Ciencia e Ingeniería de Materiales, Universidad de Costa Rica（哥斯达黎加大学材料科学与工程研究中心）；Escuela de Física, Universidad de Costa Rica（哥斯达黎加大学物理学院）
A Universal Strategy of Perovskite Ink-Substrate Interaction to Overcome the Poor Wettability of a Self-Assembled Monolayer for Reproducible Perovskite Solar Cells
已经报道了采用自组装单层（诸如Me-4PACz）作为空穴传输层的Percent太阳能电池表现出高器件效率。然而，由于钙钛矿墨水与底层Me-4PACz的相互作用较差，导致Me-4PACz上的钙钛矿润湿性较差，这对制造高效的钙钛矿器件提出了重大挑战。采用由二甲基甲酰胺（DMF）、二甲基亚砜（DMSO）和N-甲基-2-吡咯烷酮（NMP）组成的三元共溶剂体系来改善钙钛矿油墨-基底相互作用并获得均匀的钙钛矿层。与DMF、DMSO基油墨相比，NMP的包含显示钙钛矿油墨与Me-4PACz的相当高的结合能，如通过密度泛函理论计算所揭示的。通过优化的三重共溶剂比，钙钛矿器件在0.16 cm 2、0.72 cm 2和1.08 cm 2的有源面积下分别提供> 20%、19.5%和~18.5%的高功率转换效率。重要的是，这种钙钛矿油墨-基底相互作用方法是通用的，并且有助于获得其他钙钛矿组合物如MAPbI 3、FAMAPbI 3-xBrx和无MA的FACsPbI 3-xBrx的均匀层和高光伏器件性能。
Single monolayer ferromagnetic perovskite SrRuO3 with high conductivity and strong ferromagnetism
NTT Basic Research Laboratories, NTT Corporation（NTT基础实验室，NTT公司）；The University of Tokyo（东京大学）；Hiroshima University（广岛大学）；Japan Synchrotron Radiation Research Institute (JASRI)（日本同步辐射研究所）
Phenothiazine-Based Self-Assembled Monolayer with Thiophene Head Groups Minimizes Buried Interface Losses in Tin Perovskite Solar Cells
Helmholtz-Zentrum Berlin für Materialien und Energie GmbH（柏林赫尔姆霍兹材料能源中心）；University of Naples Federico II（那不勒斯费德里科二世大学）；University of Bielefeld（比勒费尔德大学）；Humboldt-Universität zu Berlin（柏林洪堡大学）；Kaunas University of Technology（考纳斯理工大学）；Istituto Italiano di Tecnologia (IIT)（意大利理工学院）
Tuning exciton emission via ferroelectric polarization at a heterogeneous interface between a monolayer transition metal dichalcogenide and a perovskite oxide membrane
