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Title: Evidence for dispersing 1D Majorana channels in an iron-based superconductor
The possible realization of Majorana fermions as quasiparticle excitations in condensed-matter physics has created much excitement. Most studies have focused on Majorana bound states; however, propagating Majorana states with linear dispersion have also been predicted. Here, we report scanning tunneling spectroscopic measurements of crystalline domain walls (DWs) in FeSe 0.45 Te 0.55 . We located DWs across which the lattice structure shifts by half a unit cell. These DWs have a finite, flat density of states inside the superconducting gap, which is a hallmark of linearly dispersing modes in one dimension. This signature is absent in DWs in the related superconductor, FeSe, which is not in the topological phase. Our combined data are consistent with the observation of dispersing Majorana states at a π-phase shift DW in a proximitized topological material.  more » « less
Award ID(s):
1720633
PAR ID:
10147051
Author(s) / Creator(s):
; ; ; ; ; ; ; ;
Date Published:
Journal Name:
Science
Volume:
367
Issue:
6473
ISSN:
0036-8075
Page Range / eLocation ID:
104 to 108
Format(s):
Medium: X
Sponsoring Org:
National Science Foundation
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