Abstract
A long-range interaction via virtual particle-hole pairs between Fermi-liquid quasiparticles leads to a nonanalytic behavior of the spin susceptibility as a function of the temperature , magnetic field , and wave number. In this paper, we study the effect of the Rashba spin-orbit interaction (SOI) on the nonanalytic behavior of for a two-dimensional electron liquid. Although the SOI breaks the SU(2) symmetry, it does not eliminate nonanalyticity but rather makes it anisotropic: while the linear scaling of with and saturates at the energy scale set by the SOI, that of continues through this energy scale until renormalization of the electron-electron interaction in the Cooper channel becomes important. We show that the renormalization group flow in the Cooper channel has a nontrivial fixed point and study the consequences of this fixed point for the nonanalytic behavior of . An immediate consequence of SOI-induced anisotropy in the nonanalytic behavior of is a possible instability of a second-order ferromagnetic quantum phase transition with respect to a first-order transition to an ferromagnetic state.
5 More- Received 11 May 2010
DOI:https://doi.org/10.1103/PhysRevB.82.115415
©2010 American Physical Society