We investigate finite temperature corrections to the Landauer formula due to electron-electron interaction within the quantum point contact.
When the Fermi level is close to the barrier height, the interaction is strongly enhanced due to semiclassical slowing of the electrons. To describe electron transport we formulate and solve a nonlocal kinetic equation for the density matrix of electrons. The correction to the conductance G is negative and strongly enhanced in the region $0.5frac{2e^2}{h}
University of New South Wales, Sydney 2052, Australia