Experiments on Spin 1/2, One Dimensional, Heisenberg Ferromagnets

自旋 1/2、一维、海森堡铁磁体的实验

• 批准号: 8702933
• 负责人: John Drumheller
• 金额: $ 22.41万
• 依托单位: Montana State University
• 依托单位国家: 美国
• 项目类别: Continuing Grant
• 财政年份: 1987
• 资助国家: 美国
• 起止时间: 1987-06-15 至 1990-11-30
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=8702933&HistoricalAwards=false
• 关键词: Experiments; Spin; Dimensional; Heisenberg; Ferromagnets

Magnetic materials are of great importance in computer memories and magnetic recording devices. It is not fully understood what controls magnetic interactions, and hence the magnetic properties of materials. The present proposal is one of a number of efforts to examine model systems in which different magnetic interactions can be isolated, studied in detail and better understood. Systems have recently been synthesized which conform to the model of a spin 1/2, one dimensional Heisenberg ferromagnet. The goal of the present proposal is to address aspects of the model that have implications for nonlinear phenomena, magnetic-structural correlations and dynamic properties. To this end, there will be a detailed study to observe the crossover from spin wave to bound magnon domination of magnetic susceptibilities. The dependence of the superexchange interaction on bond angle will also be studied by measuring the magnetic susceptibility of samples placed under uniaxial stress. Other experiments will examine the phase diagrams and the multicritical point of quasi-one- dimensional mixed metal systems showing spin glass behavior.

磁性材料在计算机存储器中非常重要 和磁记录装置。 人们还不完全理解 控制着磁性的相互作用， 的材料。 目前的建议是若干努力之一， 来研究不同磁相互作用的模型系统 可以被分离出来，详细研究，更好地理解。 最近合成的系统符合该模型 自旋为1/2的一维海森堡铁磁体 目标 本提案的主要目的是处理该模式的一些方面， 对非线性现象、磁结构 相关性和动态特性。 为此， 详细研究了自旋波到束缚波的交叉现象 磁磁化率的磁振子支配。 的依赖 超交换作用对键角的影响也将是 通过测量样品的磁化率来研究 置于单轴应力下。 其他实验将检查 相图和多临界点的准一- 三维混合金属系统显示自旋玻璃行为。