Critical behavior of density of states near Fermi energy in low-dimensional disordered metals

Abstract

We study the effect of electron-electron interaction on the one-particle density of states (\emph{DOS}) $\rho^{(d)}(\epsilon,T)$ of low-dimensional disordered metals near Fermi energy within the framework of the finite temperature conventional impurity diagram technique. We consider only diffusive limit and by a geometric re-summation of the most singular first order self-energy corrections via the Dyson equation we obtain a non-divergent solution for the \emph{DOS} at low energies, while for higher energies the well-known Altshuler-Aronov corrections are recovered. At the Fermi level $\rho^{(d)}(\epsilon,T=0)\to 0$, this indicates that interacting disordered two- and quasi-one-dimensional systems are in insulating state at zero temperature. The obtained results are in good agreement with recent tunneling experiments on two-dimensional GaAs/AlGaAs heterostructures and quasi-one-dimensional doped multiwall carbon nanotubes.