AI 中文总结
研究自旋1/2三角晶格海森堡模型中双磁子束缚态的手征增强机制，标量手征项在双磁子扇区作为定向相互作用，选择性增强特定束缚态通道，不改变单磁子谱。
AI 中文摘要
我们研究了在自旋$1/2$三角晶格$J_1$-$J_2$-$J_3$海森堡模型中加入均匀标量手征相互作用后，完全极化态之上的单磁子和双磁子激发。在海森堡模型的单磁子扇区中，通过将色散写成完全平方形式，我们识别出两个特殊的最小值流形。标量手征项在该扇区中完全抵消，使单磁子色散和单磁子不稳定性保持不变。相反，它在双磁子扇区中作为相邻翻转自旋之间的定向相互作用而存在。利用对称性适配的三角晶格谐波，我们在对称性分辨的$\mathsf{A_1}$和$\mathsf{E_2}$型分波通道中的$\Gamma$点推导出有限维能隙方程。手征耦合分裂了$\mathsf{E_2}$型扇区中两个相反相对运动手征性，从而选择性增强了一个双磁子束缚态通道。精确对角化证实了这一机制，并揭示了增强的束缚以及$M$点和不可公度总动量处的额外束缚态。我们的结果将标量手征性识别为一种有效的微观机制，可在不移动单磁子谱的情况下增强双磁子束缚，并为高场自旋向列和多极不稳定性提供了途径。
英文摘要
We study one- and two-magnon excitations above the fully polarized state of the spin-$1/2$ triangular-lattice $J_1$-$J_2$-$J_3$ Heisenberg model with a uniform scalar-chirality interaction. In the Heisenberg model, we identify two special manifolds of one-magnon minima by rewriting the dispersion in complete-square form. The chirality term cancels exactly in the one-magnon sector, leaving the dispersion and instability field unchanged, but survives in the two-magnon sector as an oriented interaction between neighboring magnons. Using symmetry-adapted lattice harmonics, we show that scalar chirality splits two-magnon states of opposite relative-motion chirality and selectively enhances the binding of one of them. It can strengthen an existing bound state, change the symmetry of the lowest magnon pair, or induce binding where none occurs without chirality. Exact diagonalization further shows that two-magnon pairing can also occur at finite total momentum. Our results identify scalar chirality as a microscopic mechanism for enhancing two-magnon pairing without modifying the one-magnon spectrum.
Comments19 pages, 9 figures, 1 table; in the 2nd version, we revised figure 5, 7 and 9, added figure 8
