Certain lattices with specific geometries have one or more spectral bands that are strictly flat, i.e. the electron energy is independent of the momentum. This can occur robustly irrespective of the specific couplings between the lattices sites due to the lattice symmetry, or it can result from fine-tuned couplings between the lattice sites. While the theoretical picture behind flat electronic bands is well-developed, experimental realization of these lattices has proven challenging. Utilizing scanning tunnelling microscopy (STM) and spectroscopy (STS), we manipulate individual vacancies in a chlorine monolayer on Cu(100) to construct various atomically precise 1D lattices with engineered flat bands. We realize experimentally both gapped and gapless flat band systems with single or multiple flat bands. We also demonstrate tuneability of the energy of the flat bands and how they can be switched "on" and "off" by breaking and restoring the symmetry of the lattice geometry. The experimental findings are corroborated by tight-binding calculations. Our results constitute the first experimental realizations of engineered flat bands in a 1D solid-state system and pave the way towards the construction of e.g. topological flat band systems and experimental tests of flat-band-assisted superconductivity in a fully controlled system.
Control of atomic reconstruction and quasi-1D excitons in strain-engineered moiré heterostructures
Ludwig-Maximilians-Universität München（慕尼黑大学）；Carl von Ossietzky University（卡尔·冯·奥西茨基大学）；Ioffe Institute（约费研究所）；Xi’an Jiaotong University（西安交通大学）；University of Göttingen（哥廷根大学）；Suzhou Institute of Nano-Tech and Nano-Bionics, Chinese Academy of Sciences (CAS)（中国科学院苏州纳米技术与纳米仿生研究所）；National Institute for Materials Science（物质材料研究机构）
Local-Antisymmetric Flat Band and Coexisting Correlated stripe charge orders in WSe2-Modulated Twisted Bilayer Graphene
School of Physics and Electronics, Hunan University（湖南大学物理与电子学院）；Greater Bay Area Innovation Institute, Hunan University（湖南大学大湾区创新研究院）；Center for Advanced Quantum Studies, School of Physics and Astronomy, Beijing Normal University（北京师范大学物理与天文学院先进量子研究中心）；Key Laboratory of Multiscale Spin Physics, Ministry of Education（教育部多尺度自旋物理重点实验室）
An atomically flat single-crystalline gold film thermometer on mica to study energy (heat) exchange at the nano-scale
在科学界对具有纳克范围内的质量的样品进行量热法有很大的兴趣。在快速增长的微纳米系统家族中，对能量（热）交换的详细了解可以提供有关纳米尺度化学和物理学的有价值的信息。具有原子平面热探针的可能性代表了附加值，因为它提供了与量热法一起执行扫描探针显微镜（SPM）的独特机会。在这里，我们报告的制造，表征和校准的原子平面，单晶金膜温度计的云母基板。用低能电子衍射（LEED）和扫描隧道显微镜（STM）对温度计表面进行了研究。温度计校准表明热交换系数为2.1 x 10^（-7）W/K，性能比以前基于Si衬底的传感器好10倍。实验装置允许在同一样品上同时研究热交换和表面物理。
Chiral Flat-Band Optical Cavity with Atomically Thin Mirrors
Joint Quantum Institute (JQI), University of Maryland（马里兰大学联合量子研究所）；Department of Materials Science and Engineering, University of Maryland（马里兰大学材料科学与工程系）；National Institute for Materials Science（国立材料研究所）；Research Center for Materials Nanoarchitectonics, National Institute for Materials Science（国立材料研究所材料纳米构筑研究中心）；Center for Functional Nanomaterials, Brookhaven National Laboratory（布鲁克海文国家实验室功能纳米材料中心）；Maryland Quantum Materials Center（马里兰量子材料中心）
Atomic-Scale Imaging of Lattice Relaxation and Topological Flat Bands in Helical Trilayer Graphene
National Institute for Materials Science（国立材料研究所）；Hefei National Laboratory（合肥国家实验室）；Shanghai Research Center for Quantum Sciences（上海量子科学研究中心）；Quantum Science Center of Guangdong-Hong Kong-Macao Greater Bay Area (Guangdong)（粤港澳大湾区量子科学中心（广东））；Southern University of Science and Technology（南方科技大学）
Electronic Properties of Graphene Encapsulated with Different Two-Dimensional Atomic Crystals
六方氮化硼是迄今为止唯一允许石墨烯器件表现出微米级弹道输运的基材。其他原子级平坦晶体能否用作制造优质石墨烯异质结构的基底？在这里，我们报告我们寻找替代基板。发现通过用二硫化钼或二硫化钨和hBN包封石墨烯制造的器件表现出约60，000 cm-1 $^{2}$ s $^{-1}$的一致高载流子迁移率。相比之下，用原子级平坦的层状氧化物（例如云母、铋锶钙铜氧化物和五氧化二钒）进行封装导致具有~ 1，000 cm $^{2}$ s $^{-1}$的迁移率的石墨烯器件的质量异常低。我们将这种差异主要归因于石墨烯、hBN和过渡金属二硫属化物之间界面处发生的自清洁。表面污染物聚集成大的口袋，允许界面的其余部分变得原子级清洁。对于原子级平坦的氧化物衬底上的石墨烯，不发生清洁过程。
Single-Crystalline Al/Ge Heterostructure with an Atomically Sharp Commensurate Interface
Beijing Academy of Quantum Information Sciences（北京量子信息科学研究院）；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、凝聚态物理国家实验室）；Peking University（北京大学）
Design and characterization of all two-dimensional fragile topological bands
ETH Zurich（苏黎世联邦理工学院）；Donostia International Physics Center（圣塞巴斯蒂安国际物理中心）；Flatiron Institute（_flatiron研究所）；University of Chicago（芝加哥大学）；National Institute for Theory and Mathematics in Biology（生物理论与数学国家研究所）；California Institute of Technology（加州理工学院）
Kagome goldene with flat bands and Dirac nodal line fermions via line-graph epitaxy
Hunan University（湖南大学）；Research Institute of Hunan University in Chongqing（重庆湖大研究院）；Institute for Research in Fundamental Sciences (IPM)（伊朗基础科学研究所）；University of Guilan（吉兰大学）
