On the dephasing time of the Chiral Metal.

In the low-dimensional disordered systems the dephasing time and the inelastic scattering tout-scattering) time are in general different. We show that in the case of the two-dimensional chiral metal which is formed at the surface of a. layered three-dimensional system, which is exhibiting the integer quantum Hall effect, these two quantities are essentially the same and their temperature dependence is T-3/2 I, particular, we show that the results obtained using the diagramatic technique and the phase uncertainty approach introduced by A. Stern et al. (Phys. Rev. A, 41 (1990) 3436) for the out-scattering and the dephasing time, respectively, coincide. We furthermore consider these quantities in the case of the three-dimensional chiral metal, where similar conclusions are reached.