  We propose a nanomechanical device which can actuate and probe a flying qubit
that can be used to facilitate quantum information transfer over a long
distance. The flying qubit is formed by a movable Cooper pair box (CPB)
consisting of a superconducting dot and a bulk superconductor which are
entangled by removing the Coulomb blockade of Cooper pair tunneling
electrostatically. We suggest that flying qubit states formed on movable CPB
can be observed in electron transport to a normal electrode via Andreev
reflections. The charge transfer due to periodic mechanical motion of CPB leads
to nonzero current at zero voltage and its coherence can be identified through
oscillatory dependence of the current on a gate voltage.
