Observation of Yu-Shiba-Rusinov-like states at the edge of CrBr3/NbSe2 heterostructure

Abstract

The hybrid ferromagnet-superconductor heterostructures have attracted extensive attention as they potentially host topological superconductivity. Relevant experimental signatures have recently been reported in CrBr3/NbSe2 ferromagnet-superconductor heterostructure, but controversies remain. Here, we reinvestigate CrBr3/NbSe2 by an ultralow temperature scanning tunneling microscope with higher spatial and energy resolutions. We find that the single-layer CrBr3 film is insulating and acts likely as a vacuum barrier, the measured superconducting gap and vortex state on it are nearly the same as those of NbSe2 substrate. Meanwhile, in-gap features are observed at the edges of CrBr3 island, which display either a zero-energy conductance peak or a pair of particle-hole symmetric bound states. They are discretely distributed at the edges of CrBr3 film, and their appearance is found closely related to the atomic lattice reconstruction near the edges. By increasing tunneling transmissivity, the zero-energy conductance peak quickly splits, while the pair of nonzero in-gap bound states first approach each other, merge, and then split again. These behaviors are unexpected for Majorana edge modes, but in consistent with the conventional Yu-Shiba-Rusinov states. Our results provide critical information for further understanding the interfacial coupling in CrBr3/NbSe2 heterostructure.

13 pages, 5 figures

References in corpus (28)

• Observation of Majorana Fermions in Ferromagnetic Atomic Chains on a Superconductor
• Topological superconductivity in a van der Waals heterostructure
• Distinguishing a Majorana zero mode using spin resolved measurements
• Multiband superconductivity with sign-preserving order parameter in kagome superconductor CsV3Sb5
• Observation of a Majorana zero mode in a topologically protected edge channel
• Topological Superconductivity induced by Ferromagnetic Metal Chains
• Strong localization of Majorana end states in chains of magnetic adatoms
• Evidence of topological Shiba bands in artificial spin chains on superconductors
• Orbital Fulde-Ferrell-Larkin-Ovchinnikov state in an Ising superconductor
• Quantized conductance of Majorana zero mode in the vortex of the topological superconductor (Li0.84Fe0.16)OHFeSe
• Quantum spins and hybridization in artificially-constructed chains of magnetic adatoms on a superconductor
• Microscopic resolution of the interplay of Kondo screening and superconducting pairing: Mn-phthalocyanine molecules adsorbed on superconducting Pb(111)
• Observation of magnetic adatom-induced Majorana vortex and its hybridization with field-induced Majorana vortex in an iron-based superconductor
• Electronic and magnetic characterization of epitaxial CrBr${}_3$ monolayers
• Controlling in-gap end states by linking nonmagnetic atoms and artificially-constructed spin chains on superconductors
• Topological metals and finite-momentum superconductors
• Two-dimensional Shiba lattices as possible platform for crystalline topological superconductivity
• Non-Majorana modes in diluted spin chains proximitized to a superconductor
• Spatially dispersing Yu-Shiba-Rusinov states in the unconventional superconductor ${\mathrm{FeTe}}_{0.55}{\mathrm{Se}}_{0.45}$
• Antiferromagnetism-driven two-dimensional topological nodal-point superconductivity
• Coexistence of Antiferromagnetism and Superconductivity in Mn/Nb(110)
• Testing the topological nature of end states in antiferromagnetic atomic chains on superconductors
• Zeeman effects on Yu-Shiba-Rusinov states
• Giant gate-tunable renormalization of spin-correlated flat-band states and bandgap in a 2D magnetic insulator
• Tracking a Spin-Polarized Superconducting Bound State across a Quantum Phase Transition
• Phase shift and magnetic anisotropy induced field splitting of impurity states in (Li1-xFex)OHFeSe superconductor
• Observation of in-gap states in a two-dimensional CrI2/NbSe2 heterostructure
• Quantum phase transition in magnetic nanographenes on a lead superconductor

Cited by in corpus (3)

• Berezinskii-Kosterlitz-Thouless transitions in a topological superconductor-ferromagnet-superconductor junction
• Scanning tunneling microscopy study of helimagnetic monolayer CrBr2 on s-wave superconductor NbSe2: a topologically trivial system due to weak interfacial coupling
• Non-Topological Edge-Localized Yu-Shiba-Rusinov States in CrBr${}_3$/NbSe${}_2$ Heterostructures