Single file diffusion in macroscopic Wigner rings
  The single file diffusion in a circular channel of millimetric charged balls is studied. The evolution in time of the mean square displacement is shown to be subdiffusive, but slower than the power-like $t^{1/2}$ behavior observed in circular colloidal systems or predicted in one-dimensional infinite systems. 
Gwennou Coupier, Michel Saint Jean, Claudine Guthmann