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Atomic-scale interface engineering of Majorana edge modes in a 2D magnet-superconductor hybrid system.

ABSTRACT: Topological superconductors are predicted to harbor exotic boundary states-Majorana zero-energy modes-whose non-Abelian braiding statistics present a new paradigm for the realization of topological quantum computing. Using low-temperature scanning tunneling spectroscopy, here, we report on the direct real-space visualization of chiral Majorana edge states in a monolayer topological superconductor, a prototypical magnet-superconductor hybrid system composed of nanoscale Fe islands of monoatomic height on a Re(0001)-O(2 × 1) surface. In particular, we demonstrate that interface engineering by an atomically thin oxide layer is crucial for driving the hybrid system into a topologically nontrivial state as confirmed by theoretical calculations of the topological invariant, the Chern number.

SUBMITTER: Palacio-Morales A

PROVIDER: S-EPMC6660210 | biostudies-literature | 2019 Jul

REPOSITORIES: biostudies-literature

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Atomic-scale interface engineering of Majorana edge modes in a 2D magnet-superconductor hybrid system.

Palacio-Morales Alexandra A Mascot Eric E Cocklin Sagen S Kim Howon H Rachel Stephan S Morr Dirk K DK Wiesendanger Roland R

Science advances 20190726 7

Topological superconductors are predicted to harbor exotic boundary states-Majorana zero-energy modes-whose non-Abelian braiding statistics present a new paradigm for the realization of topological quantum computing. Using low-temperature scanning tunneling spectroscopy, here, we report on the direct real-space visualization of chiral Majorana edge states in a monolayer topological superconductor, a prototypical magnet-superconductor hybrid system composed of nanoscale Fe islands of monoatomic h ...[more]

PMID: 31360762

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