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Soft Fermi Surfaces and Breakdown of Fermi Liquid Behavior

W. Metzner·D. Rohe·S. Andergassen
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Abstract

Electron-electron interactions can induce Fermi surface deformations which break the point-group symmetry of the lattice structure of the system. In the vicinity of such a "Pomeranchuk instability" the Fermi surface is easily deformed by anisotropic perturbations, and exhibits enhanced collective fluctuations. We show that critical Fermi surface fluctuations near a d-wave Pomeranchuk instability in two dimensions lead to large anisotropic decay rates for single-particle excitations, which destroy Fermi liquid behavior over the whole surface except at the Brillouin zone diagonal.

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W. Metzner, D. Rohe, S. Andergassen. 2003-11-22. Soft Fermi Surfaces and Breakdown of Fermi Liquid Behavior. https://doi.org/10.1103/physrevlett.91.066402

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