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Role of vertex corrections in the spin-fluctuation mediated pairing mechanism

Z. B. Huang·W. Hanke·E. Arrigoni
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Abstract

We study numerically and partly diagrammatically the renormalization of the electron-spin interaction or vertex in a two-dimensional one-band Hubbard model with spin-fluctuation momentum transfer ${\vv q}=(π,π)$. We find that the renormalized electron-spin vertex decreases quite generally with decreasing temperature at all doping densities. As a combination of two concurring effects, i.e. the decrease of the vertex and the increase of the spin susceptibility, the effective pairing interaction increases with lowering temperature in the intermediate-correlation regime, but {\it flattens off} in the strong-correlation regime. Our findings indicate that in the high-T$_c$ cuprates the pairing mediated by antiferromagnetic spin fluctuations is substantially reduced due to vertex corrections.

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Z. B. Huang, W. Hanke, E. Arrigoni. 2005-08-02. Role of vertex corrections in the spin-fluctuation mediated pairing mechanism. https://doi.org/10.1209/epl%2Fi2005-10176-1

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