NonFermiliquid theory for disordered metals near two dimensions
Abstract
We consider the Finkelstein action describing a system of spinpolarized or spinless electrons in 2+2ɛ dimensions, in the presence of disorder as well as the Coulomb interactions. We extend the renormalizationgroup analysis of our previous work and evaluate the metalinsulator transition of the electron gas to second order in an ɛ expansion. We obtain the complete scaling behavior of physical observables like the conductivity and the specific heat with varying frequency, temperature, and/or electron density. We extend the results for the interacting electron gas in 2+2ɛ dimensions to include the quantum critical behavior of the plateau transitions in the quantum Hall regime. Although these transitions have a very different microscopic origin and are controlled by a topological term in the action (θ term), the quantum critical behavior is in many ways the same in both cases. We show that the two independent critical exponents of the quantum Hall plateau transitions, previously denoted as ν and p, control not only the scaling behavior of the conductances σ_{xx} and σ_{xy} at finite temperatures T, but also the nonFermiliquid behavior of the specific heat (c_{v}~T^{p}). To extract the numerical values of ν and p it is necessary to extend the experiments on transport to include the specific heat of the electron gas.
 Publication:

Physical Review B
 Pub Date:
 August 2002
 DOI:
 10.1103/PhysRevB.66.075317
 arXiv:
 arXiv:condmat/0106446
 Bibcode:
 2002PhRvB..66g5317B
 Keywords:

 73.43.f;
 73.50.Jt;
 Quantum Hall effects;
 Galvanomagnetic and other magnetotransport effects;
 Condensed Matter  Mesoscopic Systems and Quantum Hall Effect
 EPrint:
 19 pages, 3 tables and one figure