报告人：倪斤阳

单位：西安交通大学

报告时间：2026年1月13日星期二 15:30

报告地点：知新楼C座7楼量子报告厅

邀请人：马衍东

摘要：The magnons in altermagnets exhibit chiral splitting even in the absence of spin-orbit coupling and external magnetic fields. Typically, this chiral splitting behavior can be well described by alternating isotropic spin exchanges (ISE) near the zero temperature. However, its finite-temperature dynamics, particularly when incorporating spin–orbit coupling, remains elusive. In this study, we reveal that, when including magnon–magnon interactions, long-range anisotropic spin exchange (ASE) can effectively induce chiral splitting of magnons at finite temperatures. Crucially, the ASE-induced chiral splitting competes with that arising from ISE, leading to a pronounced temperature-dependent modulation. Moreover, this competition is intimately coupled to quantum spin fluctuations, and can reverse the spin current driven by the band splitting as temperature increases. Our work uncovers the intrinsic competition governing collective spin excitations in altermagnets, providing new insights into their finite-temperature dynamical behavior.

报告人简介：倪斤阳，西安交通大学物理学院研究员，博士生导师。2021年博士毕业于复旦大学物理系，导师为向红军教授。2021年至2025年分别在 OPPO南京研究院及新加坡南洋理工大学从事研究工作，并于2025年九月入职西安交通大学。聚焦于关联磁性的理论研究，在低维量子磁性体系的基态性质、磁激发态输运机制以及相关计算方法的发展等方面取得了一些有意义的成果。近期工作包括：揭示二维阻挫磁性体系中高阶自旋相互作用的作用及其起源；发现磁振子非线性霍尔效应与磁序之间的普适关系；提出电场调控磁振子能带拓扑性质的新机制。上述研究成果以第一作者/通讯作者身份相继发表在 Phys. Rev. Lett.、Nano Lett.、Phys. Rev. B 等国际学术期刊。