661 research outputs found
Tunable hybridization of Majorana bound states at the quantum spin Hall edge
Confinement at the helical edge of a topological insulator is possible in the
presence of proximity-induced magnetic (F) or superconducting (S) order. The
interplay of both phenomena leads to the formation of localized Majorana bound
states (MBS) or likewise (under certain resonance conditions) the formation of
ordinary Andreev bound states (ABS). We investigate the properties of bound
states in junctions composed of alternating regions of F or S barriers.
Interestingly, the direction of magnetization in F regions and the relative
superconducting phase between S regions can be exploited to hybridize MBS or
ABS at will. We show that the local properties of MBS translate into a
particular nonlocal superconducting pairing amplitude. Remarkably, the symmetry
of the pairing amplitude contains information about the nature of the bound
state that it stems from. Hence, this symmetry can in principle be used to
distinguish MBS from ABS, owing to the strong connection between local density
of states and nonlocal pairing in our setup.Comment: 10 pages, 6 figure
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