Ballistic Composite Fermions in Semiconductor Nanostructures
  We report the results of two fundamental transport measurements at a Landau level filling factor $\nu$ of 1/2. The well known ballistic electron transport phenomena of quenching of the Hall effect in a mesoscopic cross-junction and negative magnetoresistance of a constriction are observed close to B~=~0 and $\nu~=~ 1/2$. The experimental results demonstrate semi-classical charge transport by composite fermions, which consist of electrons bound to an even number of flux quanta. 
J.E.F.Frost, C.-T.Liang, D.R.Mace, M.Y.Simmons, D.A.Ritchie and   M.Pepper (Cavendish Laboratory, Cambridge, United Kingdom)