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Truncation of a 2-dimensional Fermi surface due to quasiparticle gap formation at the saddle points

Nobuo Furukawa·Manfred Salmhofer·T. M. Rice
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Abstract

We study a two-dimensional Fermi liquid with a Fermi surface containing the saddle points $(π,0)$ and $(0,π)$. Including Cooper and Peierls channel contributions leads to a one-loop renormalization group flow to strong coupling for short range repulsive interactions. In a certain parameter range the characteristics of the fixed point, opening of a spin and charge gap and dominant pairing correlations are similar to those of a 2-leg ladder at half-filling. An increase of the electron density we argue leads to a truncation of the Fermi surface with only 4 disconnected arcs remaining.

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Nobuo Furukawa, Manfred Salmhofer, T. M. Rice. 1998-08-21. Truncation of a 2-dimensional Fermi surface due to quasiparticle gap formation at the saddle points. https://doi.org/10.1103/physrevlett.81.3195

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