Real-space anisotropy of the superconducting gap in the charge-density wave material 2H-NbSe2
Antonio Sanna,Camilla Pellegrini,Eva Liebhaber,Kai Rossnagel,Katharina J. Franke,E. K. U. Gross +5 more
TLDR
In this paper , a scanning tunneling microscopy (STM) and ab-initio study of the anisotropic superconductivity of 2H-NbSe 2 in the charge-density-wave (CDW) phase is presented.Abstract:
Abstract We present a scanning tunneling microscopy (STM) and ab-initio study of the anisotropic superconductivity of 2H-NbSe 2 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. read more
Citations
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Two-bands Ising superconductivity from Coulomb interactions in monolayer NbSe2
TL;DR: In this paper , the two distinct superconducting gaps, one for each spin-orbit split band, consist of a mixture of s-wave and f-wave components and their different amplitudes are due to the difference between the normal densities of states of the two bands at the Fermi level.
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Electron-phonon coupling and spin fluctuations in the Ising superconductor NbSe_2
TL;DR: In this article , first principle calculations of the EPC and also estimate coupling with spin fluctuations, including full momentum dependence, were reported, showing that EPC is strongly anisotropic, largely coming from the $$K-{K}^{{\prime} }$$.
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Effects of 3 MeV Proton Irradiation on Superconductivity and CDW in 2H-NbSe2 Single Crystals
Wenjie Li,Sunseng Pyon,Akiyoshi Yagi,Tong Ren,M. Suyama,Jiachen Wang,Yuto Kobayashi,Ayumu Takahashi,Daisuke Miyawaki,Tsuyoshi Tamegai +9 more
TL;DR: In this article , the role of superconductivity and charge-density wave (CDW) in 2H-NbSe2 single crystals irradiated by 3 MeV protons is studied.
Journal ArticleDOI
Effects of 3 MeV Proton Irradiation on Superconductivity and CDW in 2<i>H</i>-NbSe<sub>2</sub> Single Crystals
TL;DR: In this paper , the role of superconductivity and charge-density wave (CDW) in 2H-NbSe2 single crystals irradiated by 3 MeV protons is studied.
Sampling the Whole Materials Space for Conventional Superconducting Materials
TL;DR: In this article , a large scale study of conventional superconducting materials using a machine-learning accelerated high-throughput workflow is performed, where the transition temperature (Tc ) of approximately 200,000 metallic compounds is evaluated.
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