Low-temperature transport of correlated electrons

Transport properties of a single-channel Luttinger liquid impinging on a barrier have been studied for $g=1/2 - \epsilon$, where $g$ is the dimensionless interaction constant and $|\epsilon| \ll 1$. The relevant diagrams contributing to the conductance are identified and evaluated in all orders. Our approach represents a leading-log summation which is valid for sufficiently low temperature and small voltage. The asymptotic low-temperature corrections exhibit a turnover from the $T^{2/g-2}$ behavior to a universal $T^2$ law as the voltage is increased.