Symmetry-protected band degeneracy, coupled with a magnetic order, is the key to realizing novel magnetoelectric phenomena in topological magnets. While the spin-polarized nodal states have been identified to introduce extremely-sensitive electronic responses to the magnetic states, their possible role in determining magnetic ground states has remained elusive. Here, taking external pressure as a control knob, we show that a metal-insulator transition, a spin-reorientation transition, and a structural modification occur concomitantly when the nodal-line state crosses the Fermi level in a ferrimagnetic semiconductor Mn₃Si₂Te₆. These unique pressure-driven magnetic and electronic transitions, associated with the dome-shaped T_c variation up to nearly room temperature, originate from the interplay between the spin-orbit coupling of the nodal-line state and magnetic frustration of localized spins. Our findings highlight that the nodal-line states, isolated from other trivial states, can facilitate strongly tunable magnetic properties in topological magnets.

对称保护带简并与磁序相结合是在拓扑磁体中实现新型磁电现象的关键。虽然自旋极化节点态已被确定为磁态引入极其敏感的电子响应，但它们在确定磁基态中的可能作用仍然难以捉摸。在这里，以外部压力作为控制旋钮，我们发现当亚铁磁半导体 Mn ₃ Si ₂ Te中的节线态穿过费米能级时，金属-绝缘体转变、自旋重定向转变和结构修饰同时发生₆ .这些独特的压力驱动的磁和电子跃迁，与高达接近室温的圆顶形T _c变化相关，源于节点线状态的自旋轨道耦合与局部自旋的磁挫败之间的相互作用。我们的研究结果强调，与其他平凡状态隔离的节点线状态可以促进拓扑磁体中强可调的磁特性。