TY - JOUR
T1 - Topological Superconductivity on the Surface of Fe-Based Superconductors
AU - Xu, Gang
AU - Lian, Biao
AU - Tang, Peizhe
AU - Qi, Xiao Liang
AU - Zhang, Shou Cheng
N1 - Funding Information:
This work is supported by the U.S. Department of Energy, Office of Basic Energy Sciences, Division of Materials Sciences and Engineering under Contract No.DE-AC02-76SF00515, by FAME, one of six centers of STARnet, a Semiconductor Research Corporation program sponsored by MARCO and DARPA, and supported by the NSF under Grant No.DMR-1305677. G. X. would also like to thank for the support from NSF of China (11204359).
Publisher Copyright:
© 2016 American Physical Society.
PY - 2016/7/18
Y1 - 2016/7/18
N2 - As one of the simplest systems for realizing Majorana fermions, the topological superconductor plays an important role in both condensed matter physics and quantum computations. Based on ab initio calculations and the analysis of an effective 8-band model with superconducting pairing, we demonstrate that the three-dimensional extended s-wave Fe-based superconductors such as Fe1+ySe0.5Te0.5 have a metallic topologically nontrivial band structure, and exhibit a normal-topological-normal superconductivity phase transition on the (001) surface by tuning the bulk carrier doping level. In the topological superconductivity (TSC) phase, a Majorana zero mode is trapped at the end of a magnetic vortex line. We further show that the surface TSC phase only exists up to a certain bulk pairing gap, and there is a normal-topological phase transition driven by the temperature, which has not been discussed before. These results pave an effective way to realize the TSC and Majorana fermions in a large class of superconductors.
AB - As one of the simplest systems for realizing Majorana fermions, the topological superconductor plays an important role in both condensed matter physics and quantum computations. Based on ab initio calculations and the analysis of an effective 8-band model with superconducting pairing, we demonstrate that the three-dimensional extended s-wave Fe-based superconductors such as Fe1+ySe0.5Te0.5 have a metallic topologically nontrivial band structure, and exhibit a normal-topological-normal superconductivity phase transition on the (001) surface by tuning the bulk carrier doping level. In the topological superconductivity (TSC) phase, a Majorana zero mode is trapped at the end of a magnetic vortex line. We further show that the surface TSC phase only exists up to a certain bulk pairing gap, and there is a normal-topological phase transition driven by the temperature, which has not been discussed before. These results pave an effective way to realize the TSC and Majorana fermions in a large class of superconductors.
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U2 - 10.1103/PhysRevLett.117.047001
DO - 10.1103/PhysRevLett.117.047001
M3 - Article
C2 - 27494494
AN - SCOPUS:84979300768
SN - 0031-9007
VL - 117
JO - Physical review letters
JF - Physical review letters
IS - 4
M1 - 047001
ER -