Dynamics in chiral magnets -Helimagnons in MnSi under pressure: Towards the non-Fermi liquid phase

手性磁体的动力学 - 压力下 MnSi 中的 Helimagnons：走向非费米液相

• 批准号: 270344603
• 负责人: Dr. Robert Georgii
• 金额: --
• 依托单位: Institut für Theoretische Festkörperphysik (TFP)
• 依托单位国家: 德国
• 项目类别: Research Grants
• 财政年份: 2015
• 资助国家: 德国
• 起止时间: 2014-12-31 至 2020-12-31
• 项目状态: 已结题
• 来源: https://gepris.dfg.de/gepris/projekt/270344603?language=en
• 关键词: Dynamics; chiral; magnets; Helimagnons; MnSi

In the previous project we have reached a full theoretical understanding of the (B, T)-phase diagram of MnSi and its underlying dynamical processes based on only three input parameters, the strength of the DM interaction, the stiffness of the magnetic spiral under magnetic field and the anharmonicity of the magnetic spin system.This will allow us to continue in the understanding of the role of the anisotropy and the fluctuations in MnSi as we extend the parameter space to applied pressure. Here we are interested in how the magnetic spiral develops with pressure and if there is new physics when approaching the critical pressure of 14.6 kbar. We would furthermore like to explore the behaviour of MnSi under pressure and field simultaneously, eventually testing the skyrmion regime. Finally, we plan to reach the critical pressure and above both in zero field and with applied magnetic field. This will enable us to test whether the non-Fermi liquid behaviour above the critical pressure is related to the spin dynamics of the skyrmion lattice. This will help to establish a connection between magnetic fluctuations and topological magnetic structures.

在之前的项目中，我们已经对MnSi的（B，T）-相图及其基础动力学过程达到了完全的理论理解，仅基于三个输入参数，DM相互作用的强度，磁场下磁螺旋的刚度和磁自旋系统的非谐性。这将使我们能够继续理解MnSi中各向异性和涨落的作用因为我们将参数空间扩展到施加的压力。在这里，我们感兴趣的是磁螺旋如何随着压力而发展，以及当接近14.6 kbar的临界压力时是否有新的物理学。我们还想同时探索MnSi在压力和场作用下的行为，最终测试skyrmion机制。 最后，我们计划在零场和外加磁场下都达到临界压力及以上。这将使我们能够测试是否非费米液体的行为在临界压力以上的skyrmion晶格的自旋动力学。这将有助于建立磁波动和拓扑磁结构之间的联系。