Muon studies of quantum materials under extreme environments

在接下来的五年里，我的研究将集中在μ子自旋旋转/弛豫技术（µSR）在极端条件下研究新型量子材料的应用上。我的目标是了解拓扑材料，非常规超导体和磁阻材料的显着物理特性，通过应用非热扰动（化学掺杂，磁场，压力）将材料调整到量子临界状态，由量子力学和强电子相关性的影响所带来。正μ介子是一个敏感的局部探针的内部磁场在一个独特的微秒时间尺度上，并将在这项工作中利用，以了解量子材料的奇异物理性质的无序的影响。到目前为止，我已经在外加磁场和/或低温的极端环境中进行了量子材料的μ子研究。我的研究的一个新的重点将是GPa尺度上的高压能力与低温下量子材料的μ子研究的整合。高压可以用来使材料晶格中的原子更紧密地结合在一起，从而引起电子结构和磁相互作用的可调变化。这一目标将利用投资和及时完成和实施新的高动量和高亮度μ子束线在温哥华的TRIUMF。新的研究基础设施将为加拿大和国际用户提供西半球无与伦比的能力，以研究正常和极端条件下的量子系统。我的HQP和我将通过在瑞士的Paul Scherrer研究所（PSI）进行量子材料的合作实验，获得使用μ子进行高压研究的实践经验。目前，PSI是世界领先的量子材料研究流体静力高压μ子设施的所在地。此外，在过去的一年中，压电驱动的单轴压力单元被完全开发出来，并成功地用于PSI的μ子实验。在国外的研究中获得的知识对于在TRIUMF建立类似的高压研究能力将是非常宝贵的。我的团队还将获得用于对材料中的μ子停止位点进行理论计算的知识和工具，以改进对我们实验数据的分析和解释。近年来，可靠的方法计算μ子网站已被开发和应用于材料的μ子研究。

Over the next five years my research will focus on the application of the muon spin rotation/relaxation technique (µSR) to studies of novel quantum materials under extreme conditions. My goal is to understand the remarkable physical properties of topological materials, unconventional superconductors, and magnetically frustrated materials, brought about by the effects of quantum mechanics and strong electronic correlations by applying non-thermal perturbations (chemical doping, magnetic field, pressure) to tune the material towards quantum criticality. The positive muon is a sensitive local probe of internal magnetic fields on a unique microsecond time scale and will be exploited in this work to understand the effects of disorder on the exotic physical properties of quantum materials. To date I have carried out muon studies of quantum materials in the extreme environments of applied magnetic field and/or low temperature. A new emphasis of my research will be the integration of high-pressure capabilities on the GPa scale into muon studies of quantum materials at low temperatures. High pressure can be used to bring atoms in the crystal lattice of a material closer together, inducing tunable changes of the electronic structure and magnetic interactions. This objective will exploit the investment and timely completion and implementation of new high momentum and high luminosity muon beam lines at TRIUMF, Vancouver. The new research infrastructure will provide Canadian and international users with unmatched capabilities in the Western Hemisphere to study quantum systems under normal and extreme conditions. My HQP and I will gain practical experience in high pressure research using muons via collaborative experiments on quantum materials at the Paul Scherrer Institute (PSI) in Switzerland. Currently, PSI is home to the world's leading hydrostatic high-pressure muon facility for quantum materials research. Moreover, this past year a piezoelectric-driven uniaxial pressure cell was fully developed and successfully utilized in a muon experiment at PSI. The knowledge gained in this research abroad will be invaluable for establishing an analogous high-pressure research capability at TRIUMF. My team will also gain the knowledge and tools for performing theoretical calculations of muon stopping sites in materials to improve the analysis and interpretation of our experimental data. In recent years, reliable methods for calculating muon sites have been developed and applied to muon studies of materials.