  Coherent Quantum Phase Slip consists in the coherent transfer of vortices in
superfluids. We investigate this phenomenon in two miscible coherently coupled
components of a spinor Bose gas confined in a toroidal trap. After imprinting
different vortex states on each component, we demonstrate that during the whole
dynamics the system remains in a linear superposition of two current states in
spite of the non-linearity and can be mapped onto a linear Josephson problem.
We propose this system as a good candidate for the realization of a
Mooij-Harmans qubit and remark its feasibility for implementation in current
experiments with $^{87}\mbox{Rb}$, since we have used values for the physical
parameters currently available in laboratories.
