Muon Studies of Quantum Materials and Novel States of Matter

量子材料和新物态的 μ 子研究

• 批准号: RGPIN-2016-04508
• 负责人: Sonier, Jeffrey
• 金额: $ 2.91万
• 依托单位: Simon Fraser University
• 依托单位国家: 加拿大
• 项目类别: Discovery Grants Program - Individual
• 财政年份: 2016
• 资助国家: 加拿大
• 起止时间: 2016-01-01 至 2017-12-31
• 项目状态: 已结题
• 来源: https://www.nserc-crsng.gc.ca/ase-oro/Details-Detailles_eng.asp?id=615109
• 关键词: Muon; Studies; Quantum; Materials; Novel

Quantum materials comprise a wide range of scientifically fascinating and technologically important phenomena, including high-temperature superconductivity, non-Fermi liquid behaviour, colossal magnetoresistance, and countless forms of magnetism and ferroelectricity. These unusual behaviours seemingly arise from quantum fluctuations extending beyond a phase transition that has been driven to absolute zero temperature (T = 0) by a non-thermal control parameter (applied pressure, applied magnetic field or chemical manipulation of electron density). Understanding so-called quantum phase transitions (QPTs) and the accompanying emergent quantum phenomena is a grand challenge and a central thrust of modern condensed matter physics. QPTs and associated critical behaviour can be severely modified by disorder. Disorder may be inherent, intentionally introduced by changing the chemical composition, or intrinsically driven by a close competition between different ground states. In general, disorder-induced QPTs are predicted to drive correlated-electron systems to novel quantum disordered phases with rather exotic properties. The investigation of the effects of disorder on quantum critical phenomena necessitates local-probe experimental techniques that are capable of recognizing and characterizing disorder or phase separation in the quantum critical region. The muon spin rotation/relaxation (μSR) technique is well suited in this regard to provide insight on QPTs not attainable by other methods. When implanted in a material, the positive muon (μ+) serves as a local probe of internal magnetic field, allowing measurements of magnetic and superconducting properties. Moreover, μSR has a unique sensitivity to volume fractions of magnetic regions. I plan to concentrate my research on μSR investigations of quantum materials to provide a local probe’s perspective on non-thermal controlled quantum criticality. My approach will be to exploit new μSR experimental capabilities in Canada, utilize facilities abroad and forge new research partnerships to gain fundamental insight on quantum critical phenomena in a variety of strongly-correlated electron systems (e.g., topological insulators, unconventional superconductors, novel magnetically-frustrated metals). The proposed research initiatives aim to determine the extent to which phase separation is a ubiquitous phenomenon of magnetic QPTs and to elucidate novel states of matter. The knowledge gained will support quantum materials research and technology, which is a current strategic priority research area in Canada. My research plan provides a fertile HQP training ground for enhancing the workforce skills of trainees through exposure to state-of-the-art technologies, engagement in cutting-edge science, extensive collaborations, and opportunities to travel and disseminate research results.

量子材料的科学迷人和技术重要的现象这些行为是由于不超越相位过渡到绝对零温度（t = 0）的波动而引起的。 （QPTS）和随附的新兴量子现象是一个巨大的挑战，也是现代物理物理学的中心。 QPT和相关的批判性行为可以组成，或者是由不同基础状态之间的紧密竞争驱动的。 在这方面，对疾病对量子现象的影响的研究必需品是能够在技术中能够认识和表征障碍或相位分离的本地探针实验技术，这在这方面很好地提供了对其他方法无法获得的QPT的见解。 TIC场，允许测量磁性和超导性能。 我计划将我的研究集中在量子材料的研究上，以提供局部探测器对非末端受控量子效果的看法。各种密切相关的电子系统风云素，新型的磁性金属）。 拟议的倡议的目的是在加拿大获得的量子材料研究和技术方面的阶段分离是一种新的知识。最先进的，最先进的科学，广泛的合作以及旅行和展示研究结果的机会。