Muon Spin Relaxation Studies in Frustrated and/or Low Dimensional Spin Systems

Uemura μ子自旋弛豫（muSR）测量被提出用于研究几何受挫自旋系统的基态性质和自旋涨落，如Kagome晶格和三角形晶格反铁磁体锶铬(x)镓（12-x）氧（19）和锂镍氧(2)，以及低维自旋系统，包括掺杂Haldane自旋链系统（钇，钙）(2)钡镍氧(5)。自旋-佩尔斯体系（铜，锌）锗氧(3)，一维有机导体铝碳（60），自旋阶梯铜酸盐，锶（n-1）铜（n+1）氧（2n）。本提案旨在揭示所建议的自旋液体基态的细节，并阐明由于引入缺陷或掺杂载流子而导致多体单线态基态破坏的过程。muSR实验将在加拿大温哥华的TRIUMF设施进行。固体中原子排列的某些构型，如三角形或Kagome晶格，往往会阻止放置在其上的原子的磁矩对齐，从而促进磁矩（自旋）的动态波动。类似地，在自旋的低维排列中，如磁矩链，磁有序被抑制。在这些系统中，预计在低温下会出现新的磁性行为，包括出现“量子自旋液体”的可能性，这是由于量子力学效应导致的力矩的无序液体状动态状态。该提案旨在通过利用一种称为μ子自旋弛豫（muSR）的新技术来揭示这种奇异磁性行为的本质，该技术利用高强度质子加速器（加拿大温哥华的TRIUMF设施）产生的放射性基本粒子μ子来探测固体内部的磁性。

9510454 Uemura Muon spin relaxation (muSR) measurements are proposed to study ground state properties and spin fluctuations in geometrically frustrated spin systems, such as the Kagome lattice and triangular lattice antiferromagnets strontium chromium (x) gallium (12-x) oxygen (19) and lithium nickel oxygen (2), as well as in low-dimensional spin systems, including the doped Haldane spin chain system (yttrium, calcium) (2) barium nickel oxygen (5), the spin-Peierls system (copper, zinc) germanium oxygen (3), the one-dimensional organic conductor aluminum carbon (60), and the spin-ladder cuprates, strontium (n-1) copper (n+1) oxygen (2n). This proposal aims to reveal details of suggested spin-liquid ground states as well as to elucidate the process of destruction of the many-body singlet ground state due to the introduction of imperfections or doped charge carriers. The muSR experiments will be performed at the TRIUMF facility in Vancouver, Canada. %%% Certain configurations of atomic arrangements in solids, such as the triangular or Kagome lattice, tend to prevent the alignment of the magnetic moments of the atoms placed on it, promoting dynamic fluctuations of the moments (spins). Similarly, magnetic ordering is suppressed in low-dimensional arrangements of spins, such as a chain of magnetic moments. In these systems, novel magnetic behavior is expected at low temperatures, including the possibility for the occurrence of a "quantum spin liquid", which is a disordered liquid- like dynamic state of the moments due to quantum-mechanical effects. This proposal aims to reveal the nature of such exotic magnetic behavior by utilizing a novel technique called muon spin relaxation (muSR), which probes the magnetism within solids with radioactive elementary particles, muons, produced at a high-intensity proton accelerator (the TRIUMF facility in Vancouver , Canada).