Electric driving of the excited orbitals of the NV- center in the ultrastrong regime

The NV center in diamond is a versatile spin qubit widely used for nanoscale sensing of magnetic and electric fields. Under cryogenic conditions (T<7K), it displays lifetime-limited spin-selective optical transitions, which have been used for the entanglement of remote spins [1]. Those transitions however suffer from their sensitivity to electric and strain fields such that different NVs require active stabilization to interact.

Here, we show the electric dipole responsible for this instability can also be exploited for control of the optically excited states. We use microwave electric fields to drive Rabi oscillations between two optically excited orbitals (Ex, Ey) in the ultra strong regime. Photoluminescence excitation of those states show clear Rabi splitting as well as second order terms. Notably, this driving suppresses first order fluctuation of the electric field in the NV transverse plane and can be used for fast tuning of the NV optical resonance. These results open prospect for enhanced electric sensitivity and to optimize NV-NV optical entanglement.

[1] Pompili, Matteo, et al. "Realization of a multinode quantum network of remote solid-state qubits." _Science_ 372.6539 (2021): 259-264.