Resonant excitation of a single dichroic vacancy spin in silicon carbide

Color centers in solid-state hosts are very attractive systems for scalable and integrated nano photonics and quantum information architectures. The ideal system should meet three key features: first, an electron spin coherence time on the order of milliseconds to permit quantum state manipulation and coupling to surrounding nuclear spins; second, a large fraction of photons must be emitted in the zero phonon line to couple different centers to each other via spin-photon entanglement; third, excellent spectral stability. Here, we demonstrate that all three criteria are met by the dichroic vacancy defect center (V1) in 4H-SiC [1]. The V1 center is a S=3/2 spin system with well-separated optical transitions at around 860 nm [2]. We perform resonant optical excitation studies on single V1 centers to explore the ground and excited state level structures. We will also present studies on the spin dynamics under resonant excitation. We note further that no spectral diffusion has been observed. Therefore, our results pave the way for a robust and scalable quantum information platform based on color centers in silicon carbide [3]. [1] R. Nagy et al., arxiv:1707.02715 [2] M. Widmann et al., Nat. Mater. 14, 164 [3] O. O. Soykal et al., Phys. Rev. B 93, 081207(R) (2016)