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arXiv · 1512.06688

Coexistence of Nematic Order and Superconductivity in the Hubbard Model

Jan Kaczmarczyk·Tobias Schickling·Jörg Bünemann
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Abstract

We study the interplay of nematic and superconducting order in the two-dimensional Hubbard model and show that they can coexist, especially when superconductivity is not the energetically dominant phase. Due to a breaking of the $C_4$ symmetry, the coexisting phase inherently contains admixture of the $s$-wave pairing components. As a result, the superconducting gap exhibits very non-standard features including changed nodal directions. Our results also show that in the optimally doped regime the superconducting phase is typically unstable towards developing nematicity (breaking of the $C_4$ symmetry). This has implications for the cuprate high-$T_c$ superconductors, for which in this regime the so-called intertwined orders have recently been observed. Namely, the coexisting phase may be viewed as a precursor to such more involved patterns of symmetry breaking.

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Jan Kaczmarczyk, Tobias Schickling, Jörg Bünemann. 2015-12-21. Coexistence of Nematic Order and Superconductivity in the Hubbard Model. https://doi.org/10.1103/physrevb.94.085152

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