  We propose how to create, control, and read-out real-space localized spin
qubits in proximitized finite graphene nanoribbon (GNR) systems using purely
electrical methods. Our proposed nano-qubits are formed of in-gap
singlet-triplet states that emerge through the interplay of Coulomb and
relativistic spin-dependent interactions in GNRs placed on a magnetic
substrate. Application of an electric field perpendicular to the GNR
heterostructure leads to a sudden change in the proximity couplings, i.e. a
quantum quench, which enables us to deterministically rotate the nano-qubit to
any arbitrary point on the Bloch sphere. We predict these spin qubits to
undergo Rabi oscillations with optimal visibility and frequencies in excess of
10 GHz. Our findings open up a new avenue for the realization of graphene-based
quantum computing with ultra-fast all-electrical methods.
