Evidence of nodal superconductivity in monolayer 1H-TaS${}_2$ with hidden order fluctuations

Abstract

Unconventional superconductors represent one of the fundamental directions in modern quantum materials research. In particular, nodal superconductors are known to appear naturally in strongly correlated systems, including cuprate superconductors and heavy-fermion systems. Van der Waals materials hosting superconducting states are well known, yet nodal monolayer van der Waals superconductors have remained elusive. Here, using low-temperature scanning tunneling microscopy (STM) and spectroscopy (STS) experiments, we show that pristine monolayer 1H-TaS${}_2$ realizes a nodal superconducting state. By including non-magnetic disorder, we drive the nodal superconducting state to a conventional gapped s-wave state. Furthermore, we observe the emergence of many-body excitations close to the gap edge, signalling a potential unconventional pairing mechanism. Our results demonstrate the emergence of nodal superconductivity in a van der Waals monolayer, providing a building block for van der Waals heterostructures exploiting unconventional superconducting states.

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• Unconventional Superconductivity
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• Electron-phonon interaction and transport properties of metallic bulk and monolayer transition metal dichalcogenide TaS${}_2$
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• Zero-bias conductance peak in detached flakes of superconducting 2H-TaS${}_2$ probed by scanning tunneling spectroscopy
• Confinement-engineered superconductor to correlated-insulator transition in a van der Waals monolayer
• van der Waals heterostructures based on atomically-thin superconductors

Cited by in corpus (12)

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• Anharmonicity reveals the tunability of the charge density wave orders in monolayer VSe${}_2$
• Nature of the unconventional heavy fermion Kondo state in monolayer CeSiI
• Kramers nodal lines in intercalated TaS${}_2$ superconductors
• Doped Mott phase and charge correlations in monolayer 1T-NbSe${}_2$
• Nonlinear optical responses in multi-orbital topological superconductors
• Darkness in interlayer and charge density wave states of 2H-TaS2
• Friedel oscillations and chiral superconductivity in monolayer NbSe${}_2$
• Self-doped flat band and spin-triplet superconductivity in monolayer 1T-TaSe${}_{2-x}$Te${}_x$
• Twisted Nodal Superconductors
• Unconventional superconductivity in monolayer transition metal dichalcogenides
• Realization of Air-Stable Two-Dimensional Superconductor Nb2Pd3Te5 With Quasi-One-Dimensional Pair Density Modulation