All-optical control of the spin state in the NV- center in diamond

We describe an all-optical scheme for spin manipulation in the ground-state triplet of the negatively charged nitrogen-vacancy (NV) center in diamond. Virtual optical excitation from the (3)A(2) ground state into the E-3 excited state allows for spin rotations by virtue of the spin-spin interaction in the two-fold orbitally degenerate excited state. We derive an effective Hamiltonian for optically induced spin-flip transitions within the ground state spin triplet due to off-resonant optical pumping. Furthermore, we investigate the spin qubit formed by the Zeeman sublevels with spin projection m(S) = 0 and m(S) = -1 along the NV axis around the ground state level anticrossing with regard to full optical control of the electron spin.