AI 中文总结
该研究通过拓扑维格纳晶体的赝自旋相互作用模型，揭示了铁磁海森堡交换J与手性相互作用γ的竞争可稳定密度随γ/J连续调节的零场斯格明子晶体，明确了铁磁拓扑维格纳晶体的相图。
AI 中文摘要
在具有强相互作用的低密度系统中，电子预计会结晶形成维格纳固体。近年来，电子携带贝里曲率的二维系统的进展为维格纳结晶增加了拓扑维度。本文利用拓扑维格纳晶体中的赝自旋相互作用模型，证明了三角晶格上铁磁海森堡交换作用J与手性相互作用γ之间的竞争，可稳定零场下的斯格明子晶体，其密度可通过γ/J的比值连续调节。手性相互作用源于底层时间反演对称破缺维格纳晶体中的有限贝里曲率。在连续极限下，手性相互作用充当斯格明子的化学势，而非线性σ模型之外的高阶梯度项则决定斯格明子的密度。在手性耦合较大时，我们发现一种24位点的四斯格明子晶体，其每个磁单胞携带4个拓扑电荷单元，当J趋近于0时，该晶体与四亚晶格四面体序简并。我们表征了这些相的磁振子结构，并讨论了在大γ/J下可调斯格明子晶体向这些态的转变。本研究结果确立了铁磁拓扑维格纳晶体的相图。
英文摘要
In low density systems with strong interactions electrons are expected to crystallize into a Wigner solid. Recently, advances in two-dimensional systems where electrons carry Berry curvature have added a topological dimension to Wigner crystallization. Using a model for pseudospin interactions in a topological Wigner crystal, here we show that the competition between ferromagnetic Heisenberg exchange $J$ and the chiral interaction $γ$ on the triangular lattice stabilizes a zero-field skyrmion crystal whose density is continuously tunable through the ratio $γ/J$. The chiral interaction originates from finite Berry curvature in an underlying time-reversal broken Wigner crystal. In the continuum limit, the chiral interaction acts as a chemical potential for skyrmions, while higher-order gradient terms beyond the nonlinear sigma model select the skyrmion density. At large chiral coupling, we uncover a 24-site tetra-skyrmion crystal carrying four units of topological charge per magnetic unit cell, which becomes degenerate with four-sublattice tetrahedral order as $J \to 0$. We characterize the magnon structure for these phases and discuss the transition between the tunable skyrmion crystal to these states at large $γ/J$. Our results establish the phase diagram of ferromagnetic topological Wigner crystals.
Comments15 pages. Comments appreciated
