  We present a theory for a mesoscopic turnstile that produces spatially
separated streams of electrons and holes along edge states in the quantum Hall
regime. For a broad range of frequencies in the non-adiabatic regime the
turnstile operation is found to be ideal, producing one electron and one hole
per cycle. The accuracy of the turnstile operation is characterized by the
fluctuations of the transferred charge per cycle. The fluctuations are found to
be negligibly small in the ideal regime.
