We report on the layer-by-layer growth of single-crystal Al2O3 thin-films on Nb (110). Single-crystal Nb films are first prepared on A-plane sapphire, followed by the evaporation of Al in an O2 background. The first stages of Al2O3 growth are layer-by-layer with hexagonal symmetry. Electron and x-ray diffraction measurements indicate the Al2O3 initially grows clamped to the Nb lattice with a tensile strain near 10%. This strain relaxes with further deposition, and beyond about 5 nm we observe the onset of island growth. Despite the asymmetric misfit between the Al2O3 film and the Nb under-layer, the observed strain is surprisingly isotropic.
Coherently strained epitaxial YBa$_2$Cu$_3$O$_{7-δ}$ films grown on NdGaO$_3$ (110)
YBa $_2$ Cu $_3$ O $_{7-δ}$是一个很好的候选者，系统地研究高温超导性的纳米工程使用先进的外延。这些研究的一个基本前提是相干应变YBa $_2$ Cu $_3$ O $_{7-δ}$薄膜，我们在这里使用NdGaO $_3$（110）作为衬底。该膜在厚度至少为100 nm时是共格的，并且具有89 $\pm$ 1 K的临界温度。YBa $_2$ Cu $_3$ O $_{7-δ}$的$a$和$b$晶格参数与NdGaO $_3$（110）的面内晶格参数相匹配，导致YBa $_2$ Cu $_3$ O $_{7-δ}$的正交性大大降低。这些结果表明，在$_2$ O $_{7-δ}$的链层中，大量的结构无序对超导电性并不有害.
Reversible tuning of magnetic order and intrinsic superconductivity in strained FeTe films via stoichiometry control
Beijing Academy of Quantum Information Sciences（北京量子信息科学研究院）；Institute of Physics, Chinese Academy of Sciences（中国科学院物理研究所）；University of Chinese Academy of Sciences（中国科学院大学）；Renmin University of China（中国人民大学）；Shanxi Normal University（山西师范大学）；Tsinghua University（清华大学）
Jahn-Teller distortion on strained La$_3$Ni$_2$O$_7$ thin films
Kavli Institute for Theoretical Sciences, University of Chinese Academy of Sciences（中国科学院大学卡尔文理论科学研究所）；Beijing National Laboratory for Condensed Matter Physics and Institute of Physics, Chinese Academy of Sciences（中国科学院物理研究所北京凝聚态物理国家研究中心）；School of Physical Sciences, University of Chinese Academy of Sciences（中国科学院大学物理科学学院）
