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arXiv · 2605.26233

Slave-boson Formalism for Superconducting Pairing at Strong Coupling

Sarbajit Mazumdar·Jonas Issing·Jannis Seufert·David Riegler·Peter Wölfle·Ronny Thomale·Michael Klett
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Abstract

We study the emergence of superconductivity in the one-band Hubbard model using the spin-rotation-invariant Kotliar-Ruckenstein slave-boson (SB) approach. Motivated by its intrinsically renormalized mean-field ground state, we construct an effective pairing vertex from dynamical fluctuations about the saddle point. Solving the anisotropic, frequency-dependent gap equation on the square lattice, we map the pairing instabilities across doping, interaction, temperature and real-frequency gap structure that qualitatively match experimental cuprate observations. This framework merges strong-correlation SB-type renormalizations with RPA-type pairing transparency, providing a scalable route to modeling multi-orbital superconductivity at strong coupling.

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Sarbajit Mazumdar, Jonas Issing, Jannis Seufert, David Riegler, Peter Wölfle, Ronny Thomale, Michael Klett. 2026-05-25. Slave-boson Formalism for Superconducting Pairing at Strong Coupling. https://arxiv.org/abs/2605.26233

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