AI 中文总结
该研究针对MnBi2Te4拓扑相变需强外磁场的瓶颈，通过铁磁绝缘体界面磁邻近效应，提出无磁场全电开关拓扑相变的栅极可调方案，还提升了磁有序温度，为高温拓扑电子学提供可行路径。
AI 中文摘要
本征磁性拓扑绝缘体MnBi2Te4在二维极限下具有依赖厚度的轴子和量子反常霍尔（QAH）绝缘态，由反铁磁层间耦合调控。但这些相之间的可控转换通常需要超过9T的极端外磁场，限制了实际可调性。通过互补的第一性原理计算和有效哈密顿量建模，我们展示了一种无磁场、可逆的机制：利用与铁磁绝缘体界面处的磁邻近效应设计拓扑相变。铁磁绝缘体中的栅极可调磁各向异性可动态调制邻近诱导的交换偏置，实现超薄MnBi2Te4中层间耦合和带拓扑的全电开关。关键的是，长程海森堡蒙特卡洛模拟显示，封装后的MnBi2Te4薄膜的磁有序温度显著提升。通过消除高场需求并同时提高热稳定性，这种栅极可调范式解决了拓扑物理学中的关键瓶颈，为可扩展的高温拓扑电子学提供了可行路径。
英文摘要
The intrinsic magnetic topological insulator MnBi2Te4, in the two-dimensional limit, hosts thickness dependent axion and quantum anomalous Hal (QAH) insulating states governed by antiferromagnetic interlayer coupling. However, controlled interconversion between these phases typically requires extreme external magnetic fields exceeding 9 T, limiting practical tunability. Using complementary first-principles calculations and effective Hamiltonian modeling, we demonstrate a field-free, reversible mechanism to engineer topological phase transitions by exploiting magnetic proximity at the interfaces with a ferromagnetic insulator. Gate-tunable magnetic anisotropy within the ferromagnetic insulator dynamically modulates the proximity-induced exchange bias, enabling all-electric switching of interlayer coupling and band topology in ultrathin MnBi2Te4. Crucially, long-range Heisenberg Monte Carlo simulations reveal that the magnetic ordering temperature of the encapculated MnBi2Te4 film is dramatically elevated. By eliminating the high-field requirement and simultaneously improving thermal stability, this gate-tunable paradigm solves a critical bottleneck in topological physics and offers a viable route toward scalable, high-temperature topological electronics.
Comments7 pages, 3 figures, Supporting Information
