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arXiv · 2302.08517

Sublattice modulated superconductivity in the Kagome Hubbard model

Tilman Schwemmer·Hendrik Hohmann·Matteo Dürrnagel·Janik Potten·Jacob Beyer·Stephan Rachel·Yi-Ming Wu·Srinivas Raghu·Tobias Müller·Werner Hanke·Ronny Thomale
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Abstract

We identify a superconducting order featuring spatial pair modulations on the kagome lattice subject to onsite Hubbard U and nearest neighbor V interactions. Within our functional renormalization group analysis, this state appears with a concomitant d-wave superconducting (SC) instability at zero lattice momentum, where it distinguishes itself through intra-unit cell modulations of the pairing function thus breaking the discrete space group symmetry. The relative weight of the sublattice modulated superconductor (SMS) and d-wave SC is influenced by the absolute interaction strength and coupling ratio V /U . Parametrically adjacent to this domain at weak coupling, we find an intra-unit cell modulated vestigial charge density wave and an s-wave SC instability. Our study provides a microscopic setting and thorough description of this novel SMS arising within a translation symmetry broken background.

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Tilman Schwemmer, Hendrik Hohmann, Matteo Dürrnagel, Janik Potten, Jacob Beyer, Stephan Rachel, Yi-Ming Wu, Srinivas Raghu, Tobias Müller, Werner Hanke, Ronny Thomale. 2023-02-16. Sublattice modulated superconductivity in the Kagome Hubbard model. https://doi.org/10.1103/physrevb.110.024501

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