Cure to the Landau-Pomeranchuk and Associated Long-Wavelength Fermi-surface Instabilities on Lattices

C. M. Varma

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arXiv · cond-mat/0311145

Cure to the Landau-Pomeranchuk and Associated Long-Wavelength Fermi-surface Instabilities on Lattices

C. M. Varma

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Abstract

The cure to the $\ell=1$ Landau-Pomeranchuk (L-P) instabilities in translationally invariant fermions is shown to be a state with an anisotropic gap at the fermi-surface. For higher $\ell$ and for fermions on a lattice, general criteria for long wavelength instabilities and their cure are found in terms of the derivatives of the single particle self-energy with respect to momentum for spin-symmetric instabilities and with respect to magnetic field for spin-antisymmetric instabilities. The results may be relevant to identifying hidden order parameters found in many metals.

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C. M. Varma. 2003-11-25. Cure to the Landau-Pomeranchuk and Associated Long-Wavelength Fermi-surface Instabilities on Lattices. https://arxiv.org/abs/cond-mat/0311145

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