  In this paper a macroscopic quantum oscillator is introduced that consists of
a flux qubit in the form of a cantilever. The magnetic flux linked to the flux
qubit and the mechanical degrees of freedom of the cantilever are naturally
coupled. The coupling is controlled through an external magnetic field. The
ground state of the introduced flux-qubit-cantilever corresponds to a quantum
entanglement between magnetic flux and the cantilever displacement.
