Zeeman-field-induced nontrivial topological phases in a one-dimensional spin-orbit-coupled dimerized lattice

Article

关键词: MAJORANA FERMIONS;    GEOMETRIC PHASE;    SOLITONS;    SUPERCONDUCTOR;    POLARIZATION;    CONDUCTANCE;    EXCITATIONS;    INSULATORS;    CHAINS;    BANDS;   

DOI  :  10.1103/PhysRevB.94.125119

来源: SCIE

【 摘 要 】

We study theoretically the interplay effect of Zeeman field and modulated spin-orbit coupling on the topological properties of a one-dimensional dimerized lattice, known as Su-Schrieffer-Heeger model. We find that in the weak (strong) modulated spin-orbit coupling regime, trivial regions or nontrivial ones with two pairs of zero-energy states can be turned into nontrivial regions by applying a uniform (staggered) perpendicular Zeeman field through a topological phase transition. Furthermore, the resulting nontrivial phase hosting a pair of zero-energy boundary states can survive within a certain range of the perpendicular Zeeman field magnitude. Due to the effective time-reversal, particle-hole, chiral, and inversion symmetries, in the presence of either a uniform or a staggered perpendicular Zeeman field, the topological class of the system is BDI, which can be characterized by Z index. We also examine the robustness of the nontrivial phase by breaking the underlying symmetries, which results in that inversion symmetry plays an important role.

【 授权许可】

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