Single Crystal Growth at Warwick

在研究凝聚态物理中出现的问题时，高质量的单晶是必不可少的。许多感兴趣的材料往往表现出各向异性行为，这是由于它们的晶体结构和相互作用，或者由于施加磁场或压力。这些材料的基本物理特性只能通过对高质量晶体的研究来揭示。单晶生长对于英国实验室内的凝聚态物理研究具有战略重要性。欧洲、日本和美国的集团之间在这一领域的竞争非常激烈。沃里克单晶生长的努力已经成功地运行了二十多年，满足了内部和外部对各种材料单晶样品的需求。我们在这一领域多年来积累的经验使我们能够在发现新材料和奇异材料时立即站在研究这些材料的最前沿。超导和磁性小组沃里克的工作集中在强关联电子系统的研究上。在单晶上使用内部实验，辅以使用中子和X射线散射，μ子光谱学以及ARPES和高磁场测量等技术的中心设施研究，使我们能够采用多管齐下的方法来研究一系列材料。这些研究被用来对感兴趣的材料的物理特性进行统一的描述。我们建议在我们非常成功的晶体生长活动的基础上，扩大我们的能力，以解决几种新发现的材料的晶体生长问题。我们将生产高质量的氧化物、硒化物、硅化物、硼化物、金属间化合物及相关材料的单晶。这些包括各种低维和受抑磁体，稀土磁性材料，2D/层状材料，螺旋材料，奇异超导体和拓扑绝缘体。对于用浮区技术生长晶体，我们将使用我们在沃里克拥有的三台光学镜炉（两台卤素灯炉和一台氙弧灯炉）。光学镜炉使我们能够在不同的生长条件下生长晶体，包括各种气体气氛，压力高达10 bar，温度高达3000 C。当浮区技术不适合时，将使用诸如助熔剂生长、布里奇曼生长和化学气相传输的替代技术来生长单晶材料。直拉技术将用于使用四弧炉生产金属间化合物材料的单晶。生长的单晶将用于我们EPSRC资助的所有工作。与过去一样，这些晶体也将提供给英国和国际上的其他研究人员。晶体生长计划支持我们多年来建立的极其广泛的合作网络。这项工作继续刺激新的合作的形成，并使英国和国际上更广泛的材料和物理界受益。

In the study of problems that arise in condensed matter physics, high quality single crystals are essential. A number of materials of interest tend to exhibit anisotropic behaviour, either as a result of their crystal structure and interactions or as a consequence of the application of magnetic fields or pressure. The underlying physics of such materials can only be unravelled by investigations on high quality crystals. Single crystal growth is of strategic importance for the study of the physics of condensed matter within UK laboratories. Competition in this field is strong between groups in Europe, Japan and the USA. The Warwick single crystal growth effort has been operating successfully for over two decades satisfying both in-house and external demand for single crystal specimens of a very wide range of materials. Our experience in this field which has been built up over many years allows us to be at the forefront of investigations of the properties of new and exotic materials as soon as they are discovered. The work of the Superconductivity and Magnetism Group Warwick centres on the investigation of strongly correlated electron systems. The use of in-house experimentation on single crystals, complemented by studies at central facilities using techniques such as neutron and x-ray scattering, muon spectroscopy as well as ARPES and measurements in high magnetic fields enables us to adopt a multi-pronged approach to the study of a range of materials. These studies are used to arrive at a unified picture of the physics of the materials of interest.We propose to expand on our capabilities to tackle the crystal growth of several newly discovered materials, building on our extremely successful crystal growth activities. We will produce high quality single crystals of oxides, selenides, silicides, borides, inter-metallics and related materials. These include various low-dimensional and frustrated magnets, rare earth based magnetic materials, 2D/layered materials, helimagnetic materials, exotic superconductors and topological insulators. For crystal growth by the floating zone technique, we will use the three optical mirror furnaces that we have at Warwick (two halogen lamp furnaces and one xenon arc lamp furnace). The optical mirror furnaces allow us to grow crystals under different growth conditions including various gas atmospheres, in pressures of up to 10 bars and at temperatures of up to 3000 C. Alternative techniques such as flux growth, Bridgman growth and chemical vapour transport will be used for the growth of single crystal materials when the floating zone technique is not suitable. The Czochralski technique will be used to produce single crystals of inter metallic materials using the tetra-arc furnace.The single crystals grown are to be used in all of our EPSRC funded work. As in the past, the crystals will also be made available to other researchers within the UK and internationally. The crystal growth programme supports an extremely wide collaborative network that we have built up over many years. The work continues to stimulate the formation of new collaborations and benefits the wider materials and physics community in the UK and internationally.