Affiliation:
1. Nordic Institute for Theoretical Physics
Abstract
We study a model in 2+1 dimensions composed of a Fermi surface of
N_fNf
flavors of fermions coupled to scalar fluctuations near quantum critical
points (QCPs). The N_f\rightarrow0Nf→0
limit allows us to non-perturbatively calculate the long-range behavior
of fermion correlation functions. We use this to calculate charge, spin
and pair susceptibilities near different QCPs at zero and finite
temperatures, with zero and finite order parameter gaps. While
fluctuations smear out the fermionic quasiparticles, we find QCPs where
the overall effect of fluctuations leads to enhanced pairing. We also
find QCPs where the fluctuations induce spin and charge density wave
instabilities for a finite interval of order parameter fluctuation gaps
at T=0T=0.
We restore a subset of the diagrams suppressed in the
N_f\rightarrow0Nf→0
limit, all diagrams with internal fermion loops with at most 2 vertices,
and find that this does not change the long-range behavior of
correlators except right at the QCPs.
Funder
Knut och Alice Wallenbergs Stiftelse
Subject
General Physics and Astronomy
Cited by
1 articles.
订阅此论文施引文献
订阅此论文施引文献,注册后可以免费订阅5篇论文的施引文献,订阅后可以查看论文全部施引文献