arXiv:cond-mat/0010306 · Physical review. B, Condensed matter
Dynamics of fermions coupling to a U(1) gauge field in the limit e2→∞
Tai Kai Ng
Abstract
In this paper we study the properties of a gas of fermions coupling to a U(1) gauge field at wave vectors $q<\ensuremath{\Lambda}\ensuremath{\ll}{k}_{F}$ at dimensions larger than 1, where $\ensuremath{\Lambda}\ensuremath{\ll}{k}_{F}$ is a high-momentum cutoff and ${k}_{F}$ is the Fermi wave vector. In particular, we shall consider the ${e}^{2}\ensuremath{\rightarrow}\ensuremath{\infty}$ limit, where charge and current fluctuations at wave vectors $q<\ensuremath{\Lambda}$ are forbidden. By generalizing a method reported in a previous paper [Phys. Rev. B 62, 7019 (2000)], we show that the system can be described as a ``marginal'' Fermi liquid of spin $1/2;$ chargeless fermions with vanishing wave functions overlap with the bare fermions in the system.