arXivDaily arXiv每日学术速递 周一至周五更新
arXiv周末暂无论文更新,休息一下吧,周末愉快~~
arXiv 1610.04510cond-mat.str-elcond-mat.other
收藏

具有相互作用的Su-Schrieffer-Heeger链中的多空穴边缘态

Multihole edge states in Su-Schrieffer-Heeger chains with interactions

A. M. Marques, R. G. Dias

摘要:

我们解决最近邻(NN)相互作用的拓扑性质的苏-Schrieffer-Heeger(SSH)链,交替跳跃幅度t1和t2的效果。无论是数值和分析,我们表明,存在的相互作用诱导拓扑不同的制度之间的相变。在半填充SSH链中的单空穴激发的特定情况下,V=t2与t1=t2相图在相平面的对角区域具有拓扑相。在这种情况下,相互作用作为钝化电位。对于SSH链的一般填充,SSH哈密顿量的不同特征子空间可以被分类为拓扑平凡和非平凡。在大相互作用极限下详细研究了两孔情形,证明了可以将两孔SSH本征子空间映射到非相互作用的一维紧束缚模型的单粒子态中,并在具有不同跳跃常数和局部势的区域之间具有界面.在等效链中拓扑边态的存在,以及它们与原始两空穴态的对应关系,可以很容易地识别。此外,我们发现,NN相互作用的存在下产生的状态,两个孔占据两个连续的边缘状态。这种多体状态也应该发生在任意填充导致宏观空穴聚集在表面(在连续的边缘状态)的可能性。

英文摘要:

We address the effect of nearest-neighbor (NN) interactions on the topological properties of the Su-Schrieffer-Heeger (SSH) chain, with alternating hopping amplitudes t1 and t2. Both numerically and analytically, we show that the presence of interactions induces phase transitions between topologically different regimes. In the particular case of one-hole excitations in a half-filled SSH chain, the V=t2 vs. t1=t2 phase diagram has topological phases at diagonal regions of the phase plane. The interaction acts in this case as a passivation potential. For general filling of the SSH chain, different eigensubspaces of the SSH Hamiltonian may be classified as topologically trivial and non-trivial. The two-hole case is studied in detail in the large interaction limit, and we show that a mapping can be constructed of the two-hole SSH eigensubspaces into one-particle states of a non-interacting one-dimensional (1D) tight-binding model, with interfaces between regions with different hopping constants and local potentials. The presence of topological edge states in the equivalent chain can be readily identifed, as well as their correspondence to the original two-hole states. Furthermore, we found that the presence of the NN interaction generates a state where two holes occupy two consecutive edge states. Such many-body states should also occur for arbitrary filling leading to the possibility of a macroscopic hole gathering at the surface (at consecutive edge states).

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。

↑