A paramagnetic neutral V_AlO_N center in wurtzite AlN for spin qubit application

Spin-polarized electronic structures of V_AlO_N centers consisting of an aluminum vacancy and a substitutional oxygen in AlN with different charge states are studied by first-principles calculations. It is observed that a paramagnetic neutral V_AlO_N center is stable in p-type AlN. The defect center possesses a triplet ground state and a spin-conserved excited state with rather low excitation energy and its spin coherence time is in an order of second at T = 0 estimated by using a mean-field-based scheme. The results indicate that the neutral V _AlO_N center is a promising candidate for spin coherent manipulation and qubit operation.