Structure and magnetism of novel quantum and thermoelectric materials

本申请中提出的研究方案属于材料发现研究的范畴。我们将特别关注量子材料，这种材料表现出来自其组成电子的量子力学的奇异物理性质。最近引起人们极大兴趣的一类量子材料是量子自旋液体。众所周知，由于强烈的量子效应，氦即使在绝对零度下也不会变成固体。类似地，量子自旋液体中的电子自旋不能形成静态有序状态(自旋固体)。相反，量子自旋液态是由一种完全不同类型的序来描述的，称为拓扑序，这可能对构建量子计算机很有用。 另一类令人感兴趣的材料是热电材料，它们被作为清洁能源范例的关键元素进行了深入的研究；它们可以利用太阳能或余热发电，甚至可以用于制冷。最近对这些材料的兴趣主要集中在它们的高温使用上，例如汽车中的废热回收。然而，大量技术可以受益于热电材料效率的提高，这些材料适合于较低温度的应用，如电动汽车电池的热管理。 我们建议利用各种材料合成和表征方法来研究这些材料。我们计划使用各种基于同步加速器的磁x射线光谱学，例如共振非弹性x射线散射，以及国际用户设施中可用的中子光谱学方法。拟议的研究计划还将侧重于通过培训学生和博士后使用先进的X射线和中子散射实验技术来培养加拿大的材料研究人才。

The research program proposed in this application falls into the category of materials discovery research. In particular, we will focus on quantum materials, which exhibit exotic physical properties arising from quantum mechanics of their constituent electrons. One class of quantum materials which has sparked much interest recently is quantum spin liquids. It is well known that helium does not become solid even at absolute zero temperature due to strong quantum effects. Analogously, the electron spins in quantum spin liquids fail to form a static ordered state (spin solid). Instead, the quantum spin liquid state is described by a completely different type of order called topological order, which could be useful for building a quantum computer. Another class of material of interest is thermoelectric materials, which are studied intensively as a key element of the clean energy paradigm; they can generate electricity from solar or waste heat, and can be even used for refrigeration. Recent interest in these materials has been mostly focused on their high-temperature usage, such as waste heat recovery in automobiles. However, a large number of technologies can benefit from the improved efficiency of thermoelectric materials suitable for lower temperature applications such as thermal management of batteries in electric vehicles. We propose to investigate these materials utilizing various materials synthesis and characterization methods. We plan to use various synchrotron-based magnetic x-ray spectroscopy, such as resonant inelastic x-ray scattering, as well as neutron spectroscopy methods available at international user facilities. The proposed research program will also focus on developing materials research talent in Canada through training students and postdoctoral fellows in using advanced x-ray and neutron scattering experimental techniques.