Single-file diffusion in a multilayered channel

We demonstrate that strongly repelling Brownian particles confined in two-dimensional microchannels with multiple layers show single-file diffusion. At long times the mean-square displacement (MSD) is proportional to t(1/2), as in the one-dimensional case. On an intermediate timescale the MSD is further reduced. It scales with a minimal exponent that decreases with the number of layers in the channel. In the limit of infinite width of the channel, the MSD time evolution shows a crossover to a logarithmic time dependence.