电子结构和超导能隙结构是建立铁基超导体超导电机理微观理论的前提。然而，即使是最广泛研究的最佳掺杂的（Ba $_{0.6}$ K $_{0.4}$）Fe $_2$ As $_2$，其电子结构和超导能隙结构仍存在突出的争议。在这里，我们解决了这些问题进行高分辨率的角度分辨光电子能谱（ARPES）测量的最佳掺杂的（Ba $_{0.6}$ K $_{0.4}$）Fe $_2$ As $_2$超导体使用氦气灯和激光光源。我们的结果表明，在超导态的布里渊区中心附近观察到的“平带”的特点来源于超导诱导的带回弯和带从区角到中心的折叠的综合效应。在正常态和超导态中，我们都发现了带角和中心之间带折叠的直接证据。我们对平带起源的解析，使我们有可能正确地分配围绕带中心的三个类空穴带，并确定它们的超导能隙。在带角附近，我们同时观察到正常态和超导态下的一个微小的类电子带和一个M形带。所获得的间隙大小的带周围的区域角落（$\sim$ 5.5毫电子伏）是显着小于所有以前的ARPES测量。我们的结果建立了一个新的超导能隙结构附近的区域角落和解决了一些突出的争议有关的电子结构和超导能隙结构的最佳掺杂的（Ba $_{0.6}$ K $_{0.4}$）Fe $_2$ As $_2$。这些结果为研究和建立铁基超导体的超导机理提供了新的思路。
英文摘要：
The electronic structure and superconducting gap structure are prerequisites to establish microscopic theories in understanding the superconductivity mechanism of iron-based superconductors. However, even for the most extensively studied optimally-doped (Ba$_{0.6}$K$_{0.4}$)Fe$_2$As$_2$, there remain outstanding controversies on its electronic structure and superconducting gap structure. Here we resolve these issues by carrying out high-resolution angle-resolved photoemission spectroscopy (ARPES) measurements on the optimally-doped (Ba$_{0.6}$K$_{0.4}$)Fe$_2$As$_2$ superconductor using both Helium lamp and laser light sources. Our results indicate the "flat band" feature observed around the Brillouin zone center in the superconducting state originates from the combined effect of the superconductivity-induced band back-bending and the folding of a band from the zone corner to the center. We found direct evidence of the band folding between the zone corner and the center in both the normal and superconducting state. Our resolution of the origin of the flat band makes it possible to assign the three hole-like bands around the zone center and determine their superconducting gap correctly. Around the zone corner, we observe a tiny electron-like band and an M-shaped band simultaneously in both the normal and superconducting states. The obtained gap size for the bands around the zone corner ($\sim$5.5 meV) is significantly smaller than all the previous ARPES measurements. Our results establish a new superconducting gap structure around the zone corner and resolve a number of prominent controversies concerning the electronic structure and superconducting gap structure in the optimally-doped (Ba$_{0.6}$K$_{0.4}$)Fe$_2$As$_2$. They provide new insights in examining and establishing theories in understanding superconductivity mechanism in iron-based superconductors.
Increase of superconducting order parameter in the magnetic superconductor Dy0.6Y0.4Rh3.85Ru0.15B4 in a wide magnetic field range. Is it a further candidate in p-wave superconductors?
首次研究了磁性超导体Dy_（0.6）Y_（0.4）Rh_（3.85）Ru_（0.15）B_4的Andreev反射谱。结果表明，与传统的单线态超导体相比，外加磁场（最高可达0.7 Hc ~ 2）对超导体有很强的激励作用。对于某些接触获得的比率2Δ/kBTc \approx 4.0高于具有弱电子-声子相互作用的常规超导体的典型值3.52。在Dy_（0.6）Y_（0.4）Rh_（3.85）Ru_（0.15）B_4中，实现了三重态的超导配对机制。
High bias anomaly in YBa2Cu3O7/LaMnO_{3+delta}/YBa2Cu3O7 Superconductor/Ferromagnetic Insulator/Superconductor junctions: Evidence for a long-range superconducting proximity effect through the conduction band of a ferromagnetic insulator
研究了超导体/铁磁绝缘体/超导体（$_2$ O $_{7-x}$ /LaMnO $_{3+δ}$ /$_2$ O $_3$）隧道结的垂直输运特性.在一个大的偏置电压$V\sim 1$ V，我们观察到一个阶梯状的开始过电流，发生在超导转变温度$T<T_c$以下，很容易被磁场抑制。这种现象是由于非平衡电子通过Fowler-Nordheim隧穿过程注入到铁磁绝缘体导带中的一种新型的超导邻近效应。强非平衡布居的发生证实了在大偏压下的光子发射的检测。由于我们的铁磁绝缘体中的导带是强自旋极化的，所观察到的长程（20 nm）邻近效应为非传统的自旋三重态超导态提供了证据。
Structural and electrical transport properties of superconducting Au{0.7}In{0.3} films: A random array of superconductor-normal metal-superconductor (SNS) Josephson junctions
The structural and superconducting properties of Au{0.7}In{0.3} films, grown by interdiffusion of alternating Au and In layers, have been studied. The films were found to consist of a uniform solid solution of Au{0.9}In{0.1}, with excess In precipitated in the form of In-rich grains of various Au-In phases (with distinct atomic compositions), including intermetallic compounds. As the temperature was lowered, these individual grains became superconducting at a particular transition temperature (Tc), determined primarily by the atomic composition of the grain, before a fully superconducting stat…
Double-stage continuous-discontinuous superconducting phase transition in the Pauli paramagnetic limit of a 3D superconductor: the URu$%_{2}$Si$_{2}$ case
在重费米子化合物URu $_{2}$ Si $% _{2}$的混合超导（SC）态中观察到的de-Haas van-Alphen振荡的急剧抑制证实了在3D顺磁限制的超导体中由波动模糊的窄的双级SC相变的理论预测。二阶过渡到非均匀（FFLO）状态，然后通过一阶过渡到均匀的SC状态，通过使用非微扰的方法获得的预测的情况下，也被发现是一致的，最近的热导率测量上进行的这种材料。
Parameters dependent superconducting transition temperature in high temperature superconductors
School of Physics and Astronomy, Beijing Normal University（北京师范大学物理与天文学院）；Key Laboratory of Multiscale Spin Physics(Ministry of Education), Beijing Normal University（北京师范大学多尺度自旋物理教育部重点实验室）；New Cornerstone Science Laboratory, Department of Physics, School of Science, Westlake University（西湖大学理学院物理学系新基石科学实验室）；Institute for Theoretical Sciences, Westlake University（西湖大学理论科学研究院）；Key Laboratory for Quantum Materials of Zhejiang Province, School of Science, Westlake University（西湖大学理学院浙江省量子材料重点实验室）；Institute of Natural Sciences, Westlake Institute for Advanced Study（西湖高等研究院自然科学研究院）
