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arXiv · 2210.09384

Rashba spin-orbit coupling in the square lattice Hubbard model: A truncated-unity functional renormalization group study

Jacob Beyer·Jonas B. Profe·Lennart Klebl·Tilman Schwemmer·Dante M. Kennes·Ronny Thomale·Carsten Honerkamp·Stephan Rachel
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Abstract

The Rashba-Hubbard model on the square lattice is the paradigmatic case for studying the effect of spin-orbit coupling, which breaks spin and inversion symmetry, in a correlated electron system. We employ a truncated-unity variant of the functional renormalization group which allows us to analyze magnetic and superconducting instabilities on equal footing. We derive phase diagrams depending on the strengths of Rasbha spin-orbit coupling, real second-neighbor hopping and electron filling. We find commensurate and incommensurate magnetic phases which compete with d-wave superconductivity. Due to the breaking of inversion symmetry, singlet and triplet components mix; we quantify the mixing of d-wave singlet pairing with f-wave triplet pairing.

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Jacob Beyer, Jonas B. Profe, Lennart Klebl, Tilman Schwemmer, Dante M. Kennes, Ronny Thomale, Carsten Honerkamp, Stephan Rachel. 2022-10-17. Rashba spin-orbit coupling in the square lattice Hubbard model: A truncated-unity functional renormalization group study. https://doi.org/10.1103/physrevb.107.125115

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