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arXiv 2007.11719cond-mat.str-el
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密度波介导的Dzyaloshinskiii-Moriya相互作用

Density Wave Mediated Dzyaloshinskii-Moriya Interactions

Ian E. Powell, Steven Durr, Nicholas Rombes, Sudip Chakravarty

摘要:

我们研究了密度波态对正方晶格局域自旋的影响。我们发现,拓扑非平凡的密度波态可以诱导稳定的Dzyaloshinskiii-Moriya(DM)的相互作用之间的局域自旋的存在下的外部磁场的晶格,我们研究了由此产生的自旋模型的反铁磁和铁磁背景。虽然密度波态本身可以有助于热霍尔效应,如Li和Lee(arXiv:1905.04248v3)所示,但对称性考虑排除了所产生的自旋激发引起进一步的热霍尔效应。我们利用Holstein-Primakoff(HP)替代的经典平均场基态计算磁振子色散的LSCO和发现,密度波诱导一个弱的$d_{x^2-y^2}$各向异性,计算非阿贝尔Berry曲率为这个磁振子分支,我们明确地表明,磁振子贡献$κ_{xy}$为零。最后,我们计算了铁磁背景的拓扑密度波对磁基态能量、自旋倾斜角和自旋波色散的修正。我们发现,在HP玻色子的线性项可以影响临界行为,以前在文献中忽略了一点。

英文摘要:

We investigate the effect that density wave states have on the localized spins of a square lattice. We find that topologically nontrivial density wave states can induce stable Dzyaloshinskii-Moriya (DM) interactions among the localized spins of the lattice in the presence of an external magnetic field, and we study the resulting spin models for both antiferromagnetic and ferromagnetic backgrounds. While the density wave state itself can contribute to the the thermal Hall effect, as shown by Li & Lee (arXiv:1905.04248v3), symmetry considerations preclude the resulting spin excitations from inducing a further thermal Hall effect. We utilize a Holstein-Primakoff (HP) substitution about the classical mean-field ground state to calculate the magnon dispersion for LSCO and find that the density wave induces a weak $d_{x^2-y^2}$ anisotropy; upon calculating the non-Abelian Berry curvature for this magnon branch we show explicitly that the magnon contribution to $κ_{xy}$ is zero. Finally, we calculate corrections to the magnetic ground state energy, spin canting angles, and the spin-wave dispersion due to the topological density wave for ferromagnetic backgrounds. We find that terms linear in the HP bosons can affect the critical behavior, a point previously overlooked in the literature.

机构、总结、中文摘要均由AI分析而来,可能存在错误,请以论文正文为准。

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