arXiv:1801.06571 · Physical review. B./Physical review. B
Conditions for l=1 Pomeranchuk instability in a Fermi liquid
Yiming Wu, Avraham Klein, Andrey V. Chubukov
Abstract
In a Fermi liquid, the stability of the Fermi surface to deformation is encoded in the angular moments of the interaction between quasiparticles via the Pomeranchuk criterion ${F}_{l}$ $\ensuremath{\ge}$ $-1$. Interestingly, charge and spin conservation prevent interactions from destabilizing the $l$=1 channel even when ${F}_{l}$ = -1, indicating that high-energy processes play a nontrivial role in the low-energy Fermi liquid dynamics. The authors identify, analytically and numerically, that conservation laws imply an equivalence between processes near and away from the Fermi surface, preventing $l$=1 instabilities. Then, they construct $l$=1 order parameters without this equivalence, identifying possible novel instabilities in strongly correlated electron systems.