  A mesoscopic oscillator in U-shape has been proposed and studied. Making use
of a magnetic flux together with a potential of confinement, the electron
contained in the oscillator has been localized initially and an amount of
energy has been thereby stored. Then a sudden cancellation of both the
potential and the flux may cause an initial current which initiates a periodic
motion of the electron from one end of the U-oscillator to the opposite end,
and repeatedly. The period is adjustable. The current associated with the
periodic motion can be tuned very strong (say, more than two orders larger than
the current of the usual Aharonov-Bohm oscillation). Related theory and
numerical results are presented.
