半导体范德华异质双层中拓扑能带的Floquet工程
Floquet engineering of topological bands in semiconductor van der Waals heterobilayers
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中文总结 AI 辅助
该研究利用Floquet形式理论，通过光周期驱动实现了半导体范德华异质双层的拓扑相变，获得高陈数拓扑相，为固态驱动拓扑态研究提供了候选材料。
中文摘要 AI 辅助
我们证明，近红外至可见光的周期驱动会在过渡金属二硫化物（TMD）异质双层的光子修饰能带结构中引发拓扑相变。我们将Floquet形式理论应用于光耦合的最低阶k·p哈密顿量，得到了一个有效的四带模型，该模型能准确捕捉II型TMD异质双层在第一光子共振附近的核心光子修饰能带。零光子与一光子区之间的交叉会有效反转能带，产生陈数高达±2、能隙约10 meV的拓扑相。我们的结果确立了TMD作为工程化高陈数能带的理想候选材料，并为探索固态介质中的驱动拓扑态奠定了基础。
英文摘要
We show that periodic driving with near-infrared to visible light drives topological phase transitions in the photon-dressed band structure of transition-metal dichalcogenide heterobilayers. We apply the Floquet formalism to a light-coupled lowest-order $\mathbf{k}\cdot\mathbf{p}$ Hamiltonian, and obtain an effective four-band model that correctly captures the essential photon-dressed bands of type-II TMD heterobilayers in the vicinity of the first photon resonance. Crossings between the zero- and one-photon sectors effectively invert the bands, yielding topological phases with Chern numbers up to $\pm 2$ and gaps of order 10 meV. Our results establish TMDs as prime candidates for engineering bands with higher Chern numbers, and exploring driven topological states in solid state media.
