Find Paper, Faster
Example:10.1021/acsami.1c06204 or Chem. Rev., 2007, 107, 2411-2502
Conditions forl=1Pomeranchuk instability in a Fermi liquid
Physical Review B  (IF4.036),  Pub Date : 2018-04-02, DOI: 10.1103/physrevb.97.165101
Yi-Ming Wu,Avraham Klein,Andrey V. Chubukov

We perform a microscopic analysis of how the constraints imposed by conservation laws affect q=0 Pomeranchuk instabilities in a Fermi liquid. The conventional view is that these instabilities are determined by the static interaction between low-energy quasiparticles near the Fermi surface, in the limit of vanishing momentum transfer q. The condition for a Pomeranchuk instability is set by Flc(s)=1, where Flc(s) (a Landau parameter) is a properly normalized partial component of the antisymmetrized static interaction F(k,k+q;p,pq) in a charge (c) or spin (s) subchannel with angular momentum l. However, it is known that conservation laws for total spin and charge prevent Pomeranchuk instabilities for l=1 spin- and charge-current order parameters. Our study aims to understand whether this holds only for these special forms of l=1 order parameters or is a more generic result. To this end we perform a diagrammatic analysis of spin and charge susceptibilities for charge and spin density order parameters, as well as perturbative calculations to second order in the Hubbard U. We argue that for l=1 spin-current and charge-current order parameters, certain vertex functions, which are determined by high-energy fermions, vanish at Fl=1c(s)=1, preventing a Pomeranchuk instability from taking place. For an order parameter with a generic l=1 form factor, the vertex function is not expressed in terms of Fl=1c(s), and a Pomeranchuk instability may occur when F1c(s)=1. We argue that for other values of l, a Pomeranchuk instability may occur at Flc(s)=1 for an order parameter with any form factor.