Coordination Funds

二维(2D)材料是厚度只有一个原子或极少原子的晶体。在这类材料中最突出的代表石墨烯被发现后，还发现了许多其他的2D晶体。它们经常表现出三维实体中没有的有趣特性。此外，2D晶体的良好堆积可以导致新的物质状态，即使单独的层只被范德华(VDW)相互作用弱束缚。2018年发表的最令人印象深刻的例子是双层石墨烯转变为超导体，此时两层石墨烯被扭曲了约1.1度的“魔角”。由于2D材料的大量研究工作，这种精细的结构操纵成为可能，为研究所谓的邻近效应所迫使的相变打开了大门。例如，已经观察到Mott绝缘体和非传统超导状态之间的相变到二维铁磁相或半导体-金属相变。此外，VDW异质结还提供了丰富的光学和光电性质，如层间激子和三子。具有不同性质的2D晶体的组合，例如2D超导体和2D拓扑绝缘体，可以打开像Majorana费米子这样的奇异物理现象的大门。优先计划2244“2D材料：VDW[异质]结构的物理”的目标是结合德国科学界的研究努力和专业知识，解决关于堆叠2D材料的许多公开的基本问题。PP 2244有以下三个目标：目标1：研究层间相互作用对2D VDW材料的电子和输运性质的影响。目的2：研究二维VDW材料层间相互作用引起的光学性质。目的3：研究2D VDW材料中导致奇异效应的集体现象和相关现象。为了确保密切合作，PP 2244由协调办公室陪同。该办公室将负责为博士生和博士后组织暑期学校，为中心所有成员和相关成员举办培训活动、性别平等活动和科学讲习班。此外，还提供了参与项目之间的博士生交流计划以及青年科学家的启动资金。PP 2244的科学工作由一个指导委员会陪同。

Two-dimensional (2D) materials are crystals with a thickness of only one or very few atoms. After the discovery of graphene, the most prominent representative of this class of materials, many other 2D crystals have been identified. They often exhibit intriguing properties that have no counterpart in three-dimensional solids. Furthermore, well-defined stacking of 2D crystals can lead to new states of matter, even when the individual layers are only weakly bound by van der Waals (vdW) interactions. The most impressive example published in 2018 is the transformation of bilayer graphene into a superconductor when the layers are twisted by a "magic angle" of about 1.1 degrees. Such delicate structural manipulation has become possible thanks to massive research efforts in 2D materials, opening the door to the study of phase transitions forced by the so-called proximity effect. For example, phase transitions between a Mott insulator and an unconventional superconducting state to a 2D ferromagnetic phase or semiconductor-metal transitions have been observed. In addition, vdW heterostructures offer rich optical and optoelectronic properties, such as interlayer excitons and trions. The combination of 2D crystals with different properties, e.g., a 2D superconductor and a 2D topological insulator, can open the door to exotic physical phenomena such as Majorana fermions. The goal of Priority Program 2244 "2D Materials: Physics of vdW [Hetero]Structures" is to combine research efforts and expertise in the German scientific community to address the many open fundamental questions about stacked 2D materials. PP 2244 has the following three goals: Aim 1: Investigate the effects of interlayer interactions on electronic and transport properties in 2D vdW materials. Aim 2: Investigate the optical properties resulting from interlayer interactions in 2D vdW materials. Aim 3: Investigate collective and correlated phenomena leading to exotic effects in 2D vdW materials. To ensure a close collaboration, PP 2244 is accompanied by a coordination office. This office will take care of the organization of summer schools for PhD students and postdocs, training events, gender equality activities and scientific workshops for all members and associated members of the focus. Furthermore, a program for doctoral student exchange between the participating projects as well as start-up funding for young scientists is offered. The scientific work of PP 2244 is accompanied by a steering committee.