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arXiv · 2212.13603

Tuning quantum paramagnetism and d-wave superconductivity in single-layer iron chalcogenides by chemical pressure

Qiang Zou·Basu Dev Oli·Huimin Zhang·Tatsuya Shishidou·Daniel Agterberg·Michael Weinert·Lian Li
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Abstract

By substituting S into single-layer FeSe/SrTiO3, chemical pressure is applied to tune its paramagnetic state that is modeled as an incoherent superposition of spin-spiral states. The resulting electronic bands resemble an ordered checkerboard antiferromagnetic structure, consistent with angle-resolved photoemission spectroscopy measurements. Scanning tunneling spectroscopy reveals a gap evolving from U-shaped for FeSe to V-shaped for FeS with decreasing size, attributed to a d-wave superconducting state for which nodes emerge once the gap size is smaller than the effective spin-orbit coupling.

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Qiang Zou, Basu Dev Oli, Huimin Zhang, Tatsuya Shishidou, Daniel Agterberg, Michael Weinert, Lian Li. 2022-12-27. Tuning quantum paramagnetism and d-wave superconductivity in single-layer iron chalcogenides by chemical pressure. https://arxiv.org/abs/2212.13603

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