Electronelectron interactions in disordered metals: Keldysh formalism
Abstract
We develop a field theory formalism for the disordered interacting electron liquid in the dynamical Keldysh formulation. This formalism is an alternative to the previously used replica technique. In addition, it naturally allows for the treatment of nonequilibrium effects. Employing the gauge invariance of the theory and carefully choosing the saddle point in the Qmatrix manifold, we separate purely phase effects of the fluctuating potential from the ones that change quasiparticle dynamics. As a result, the cancellation of superdivergent diagrams (double logarithms in d=2) is automatically built into the formalism. As a byproduct we derive a nonperturbative expression for the singleparticle density of states. The remaining lowenergy σ model describes the quantum fluctuations of the electron distribution function. Its saddlepoint equation appears to be the quantum kinetic equation with the appropriate collision integral along with collisionless terms. The AltshulerAronov corrections to the conductivity are shown to arise from the oneloop quantum fluctuation effects.
 Publication:

Physical Review B
 Pub Date:
 July 1999
 DOI:
 10.1103/PhysRevB.60.2218
 arXiv:
 arXiv:condmat/9810191
 Bibcode:
 1999PhRvB..60.2218K
 Keywords:

 71.10.Ca;
 71.23.An;
 72.10.Bg;
 Electron gas Fermi gas;
 Theories and models;
 localized states;
 General formulation of transport theory;
 Condensed Matter  Disordered Systems and Neural Networks
 EPrint:
 RevTeX, 22 pages with 6 figures