AI 中文总结
该研究发现Al取代铽铁石榴石的塞曼-交换阻挫可使相邻Pt层产生巨大非线性霍尔响应，通过实验和模拟确定焦耳热为谐波响应的驱动源，为补偿型铁磁体非线性磁输运提供了新途径。
AI 中文摘要
竞争型磁相互作用可产生亚稳态或不稳定态，使磁系统对外界扰动高度敏感。本研究中，成分沿厚度方向存在梯度的Al取代铽铁石榴石中的塞曼-交换阻挫，会在相邻的Pt层中引发巨大的非线性霍尔响应。在磁补偿附近，场诱导的自旋翻转转变伴随异常大的高阶奇次谐波电压，其中三次、五次和七次谐波的振幅可与一次谐波相当。场、温度和电流的依赖关系共同确定焦耳热是谐波响应的参数驱动源。宏自旋链模拟进一步表明，电流诱导的热调制会周期性地将界面Fe磁化强度在交换主导和塞曼主导态之间切换，并重现观测到的谐波信号。这些结果展示了阻挫如何将微弱的热扰动转化为巨大的非线性电响应，为补偿型铁磁体中的非线性磁输运提供了一条途径。
英文摘要
Competing magnetic interactions can create metastable or unstable states and render magnetic systems highly susceptible to external perturbations. Here we show that Zeeman-exchange frustration in an Al-substituted terbium iron garnet with a compositional gradient across its thickness gives rise to a giant nonlinear Hall response in an adjacent Pt layer. Near magnetic compensation, a field-induced spin-flip transition is accompanied by unusually large higher-order odd harmonic voltages, with the third, fifth, and seventh harmonics reaching amplitudes comparable to that of the first harmonic. The field, temperature, and current dependences collectively identify Joule heating as the parametric drive of the harmonic response. Macrospin-chain simulations further show that current-induced thermal modulation periodically switches the interfacial Fe magnetization between exchange- and Zeeman-dominated states and reproduces the observed harmonic signals. These results demonstrate how frustration can convert a weak thermal perturbation into a large nonlinear electrical response, providing a route to nonlinear magnetotransport in compensated ferrimagnets.
