The nitrogen-vacancy (NV) center spin represents an appealing candidate for quantum information processing. Besides the widely used microwave control, its coherent manipulation may also be achieved using a laser as mediated by the excited energy levels. Nevertheless, the multiple levels of the excited state of the NV center spin make the coherent transition process become complex and may affect the fidelity of coherent manipulation. Here, we adopt the strategy of optimal quantum control to accelerate coherent-state transfer in the ground-state manifold of the NV center spin using a laser. The results demonstrate improved performance in both the speed and the fidelity of coherent-state transfer which will be useful for optical control of the NV center spin in diamond.

Reference: Optimal quantum optical control of spin in diamond, Jiazhao Tian, Tianyi Du, Yu Liu, Haibin Liu, Fangzhou Jin, Ressa S. Said, and Jianming Cai, Phys. Rev. A 100, 012110 (2019).