We study topological vortex phases in iron-based superconductors. Besides the previously known vortex end Majorana zero modes(MZMs) phase stemming from the existence of a three dimensional(3 D) strong topological insu...We study topological vortex phases in iron-based superconductors. Besides the previously known vortex end Majorana zero modes(MZMs) phase stemming from the existence of a three dimensional(3 D) strong topological insulator state, we show that there is another topologically nontrivial phase as iron-based superconductors can be doped superconducting 3 D weak topological insulators(WTIs). The vortex bound states in a superconducting 3 D WTI exhibit two different types of quantum states, a robust nodal superconducting phase with pairs of bulk MZMs and a full-gap topologically nontrivial superconducting phase which has single vortex end MZM in a certain range of doping level. Moreover, we predict and summarize various topological phases in iron-based superconductors, and find that carrier doping and interlayer coupling can drive systems to have phase transitions between these different topological phases.展开更多
基金supported by the National Basic Research Program of China (2014CB921203, 2015CB921300, and 2017YFA0303100)the National Natural Science Foundation of China (11334012 and 11674278)the Strategic Priority Research Program of CAS (XDB07000000)
文摘We study topological vortex phases in iron-based superconductors. Besides the previously known vortex end Majorana zero modes(MZMs) phase stemming from the existence of a three dimensional(3 D) strong topological insulator state, we show that there is another topologically nontrivial phase as iron-based superconductors can be doped superconducting 3 D weak topological insulators(WTIs). The vortex bound states in a superconducting 3 D WTI exhibit two different types of quantum states, a robust nodal superconducting phase with pairs of bulk MZMs and a full-gap topologically nontrivial superconducting phase which has single vortex end MZM in a certain range of doping level. Moreover, we predict and summarize various topological phases in iron-based superconductors, and find that carrier doping and interlayer coupling can drive systems to have phase transitions between these different topological phases.
