Real-space anisotropy of the superconducting gap in the charge-density wave 
material 2H-NbSe2

Sanna, Antonio; Pellegrini, Camilla; Liebhaber, Eva; Rossnagel, Kai; Franke, Katharina J.; Gross, E. K. U.

doi:10.1038/s41535-021-00412-8

Item

ITEM ACTIONSEXPORT

Add to Basket

Local TagsRelease HistoryDetailsSummary

Released

Journal Article

Real-space anisotropy of the superconducting gap in the charge-density wave material 2H-NbSe₂

MPS-Authors

/persons/resource/persons260861

Sanna, Antonio
Max Planck Institute of Microstructure Physics, Max Planck Society;

External Resource

https://doi.org/10.1038/s41535-021-00412-8
(Publisher version)

Fulltext (restricted access)

There are currently no full texts shared for your IP range.

Fulltext (public)

s41535-021-00412-8.pdf
(Publisher version), 5MB

Supplementary Material (public)

There is no public supplementary material available

Citation

Sanna, A., Pellegrini, C., Liebhaber, E., Rossnagel, K., Franke, K. J., & Gross, E. K. U. (2022). Real-space anisotropy of the superconducting gap in the charge-density wave material 2H-NbSe₂. npj Quantum Materials, 7: 6. doi:10.1038/s41535-021-00412-8.

Cite as: https://hdl.handle.net/21.11116/0000-000A-028A-8

Abstract

We present a scanning tunneling microscopy (STM) and ab-initio study of the anisotropic superconductivity of 2H-NbSe₂ in the charge-density-wave (CDW) phase. Differential-conductance spectra show a clear double-peak structure, which is well reproduced by density functional theory simulations enabling full k- and real-space resolution of the superconducting gap. The hollow-centered (HC) and chalcogen-centered (CC) CDW patterns observed in the experiment are mapped onto separate van der Waals layers with different electronic properties. We identify the CC layer as the high-gap region responsible for the main STM peak. Remarkably, this region belongs to the same Fermi surface sheet that is broken by the CDW gap opening. Simulations reveal a highly anisotropic distribution of the superconducting gap within single Fermi sheets, setting aside the proposed scenario of a two-gap superconductivity. Our results point to a spatially localized competition between superconductivity and CDW involving the HC regions of the crystal.