Spatially intertwined superconductivity and charge order in 1T-TaSSe revealed by scanning tunneling spectroscopy

Yaroslav A. Gerasimenko; Marion A. van Midden; Petra Šutar; Zvonko Jagličić; Erik Zupanič; Dragan Mihailovic

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arXiv · 2109.14585

Spatially intertwined superconductivity and charge order in 1T-TaSSe revealed by scanning tunneling spectroscopy

Yaroslav A. Gerasimenko·Marion A. van Midden·Petra Šutar·Zvonko Jagličić·Erik Zupanič·Dragan Mihailovic

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Abstract

The interplay of different emergent phenomena -- superconductivity (SC) and domain formation -- appearing on different spatial and energy scales are investigated using high-resolution scanning tunneling spectroscopy (STS) in the prototypical transition metal dichalcogenide superconductor $1T$-TaSSe single crystals ($T_{SC} = 3.2$ K) at temperatures from 1 to 20 K. Our major observation is that while the SC gap size smoothly varies on the scale of $\lesssim 10$ nm, its spatial distribution is not correlated to the domain structure. On the other hand, there is statistically significant correlation of the SC gap $\Delta_{SC}$ with spectral weight of the narrow band at the Fermi level formed from the same Ta $5d$ orbitals as the Mott-Hubbard band. We show that the narrow band follows the evolution of Hubbard bands in space, proving unambiguously its relation to the charge order. The correlations between the two suggest a non-trivial link between rapidly spatially varying charge order and superconductivity common in many quantum materials, and high-temperature superconductors in particular.

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Yaroslav A. Gerasimenko, Marion A. van Midden, Petra Šutar, Zvonko Jagličić, Erik Zupanič, Dragan Mihailovic. 2021-09-29. Spatially intertwined superconductivity and charge order in 1T-TaSSe revealed by scanning tunneling spectroscopy. https://arxiv.org/abs/2109.14585

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