Controllable Majorana fermions on domain walls of a magnetic topological insulator

Abstract

We propose to realize a one-dimensional chiral topological superconducting state at the magnetic domain walls stripe of a magnetic topological insulator coupled with a conventional s-wave superconductor. The localized Majorana zero modes can be constructed in a reconfigurable manner through magnetic domain writing by magnetic force microscopy. This proposal could be further extended to the Majorana zero modes at domain walls on superconducting spin-helical Dirac surface states, and may be applicable to the two-dimensional time-reversal invariant topological superconductor on FeTe0.5Se0.5 surface.

Majorana-induced DC Shapiro steps in topological Josephson junctions

“…Importantly, singleelectron tunneling into a pair of MBS within a TJJ leads to the fractional Josephson effect [26][27][28][29], recently confirmed by experiments [30][31][32][33][34] with missing odd Shapiro steps. These results, together with other seminal experimental observations [11,12,14,35], have deeply strengthened the evidence for MBS. However, a compelling proof of their non-Abelian nature is still lacking.…”

Theory of the Josephson current on a magnetically doped topological insulator

“…A possible alternative to the FI/SC junction is a superconducting junction on a magnetically doped TI. There are several theoretical works on systems with coexisting magnetization and superconducting pairing in the same spatial region 14,[26][27][28][29] . Chiral Majorana modes are predicted to appear in such systems.…”

Probing the Majorana bound states in a hybrid nanowire double-quantum-dot system by scanning tunneling microscopy*

“…[50] On the theoretical side, the possibility to detect the spatial profile of Majorana fermions by using STM tips that are made of either a normal or a superconducting material have also been investigated, but no quantum dot is taken into account. [51][52][53][54] Motivated by both advanced quantum transport measurements for MBSs through QD coupled with topological superconducting nanowires [15,16] and dramatic STM measurements of MBSs on the surfaces of topological superconductors, [43,44] we would like to theoretically consider a model which is composed of an STM tip and DQDs coupled to the ends of nanowire where MBSs are induced due to the proximity effect of superconductivity, see Fig. 1.…”