Field-free platform for topological zero-energy mode in superconductors LiFeAs and PbTaSe${}_2$

Abstract

Superconducting materials exhibiting topological properties are emerging as an exciting platform to realize fundamentally new excitations from topological quantum states of matter. In this work, we explore the possibility of a field-free platform for generating Majorana zero energy excitations by depositing magnetic Fe impurities on the surface of candidate topological superconductors, LiFeAs and PbTaSe${}_2$. We use scanning tunneling microscopy to probe localized states induced at the Fe adatoms on the atomic scale and at sub-Kelvin temperatures. We find that each Fe adatom generates a striking zero-energy bound state inside the superconducting gap, which do not split in magnetic fields up to 8T, underlining a nontrivial topological origin. Our findings point to magnetic Fe adatoms evaporated on bulk superconductors with topological surface states as a new platform for exploring Majorana zero modes and quantum information science under field-free conditions.

arXiv comment11 pages, 3 figures

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Cited by in corpus (19)

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• Probing topological quantum matter with scanning tunnelling microscopy
• Ordered and tunable Majorana-zero-mode lattice in naturally strained LiFeAs
• Tunable vortex Majorana zero modes in LiFeAs superconductor
• Observation of magnetic adatom-induced Majorana vortex and its hybridization with field-induced Majorana vortex in an iron-based superconductor
• Yu-Shiba-Rusinov states in real metals
• Emergent vortex Majorana zero mode in iron-based superconductors
• Enhanced anisotropic superconductivity in the topological nodal-line semimetal InxTaS2
• Orbital selectivity of layer resolved tunneling on iron superconductor Ba0.6K0.4Fe2As2
• The Three-Dimensional Electronic Structure of LiFeAs: Strong-coupling Superconductivity and Topology in the Iron Pnictides
• Observation of in-gap states in a two-dimensional CrI2/NbSe2 heterostructure
• Ferromagnetic Impurity Induced Majorana Zero Mode in Iron-Based Superconductor
• Fully gapped superconductivity without sign reversal in the topological superconductor PbTaSe${}_2$
• Experimental detection of topological electronic state and large linear magnetoresistance in $SrS{n}_4$ superconductor
• Doping effects on charge density instability in non-centrosymmetric PbxTaSe2
• Robust topological state against magnetic impurities observed in superconductor PbTaSe2
• Intrinsic chiral topological superconductor thin films
• Detecting and Distinguishing Majorana Zero Modes with the Scanning Tunneling Microscope
• A mesoscopic device for a realization of the Topological Kondo effect