Spin Polarization, Electron–Phonon Coupling, and Zero-Phonon Line of the NV Center in 3C-SiC

International audience; The nitrogen-vacancy (NV) center in 3C-SiC, the analog of the NV center in diamond, has recently emerged as a solid-state qubit with competitive properties and significant technological advantages. Combining first-principles calculations and magnetic resonance spectroscopy we provide thorough insight in its magneto-optical properties. By applying resonantly excited electron paramagnetic resonance spectroscopy, we identified the zero-phonon absorption line of the 3 A 2 → 3 E transition at 1289 nm (within the telecom Oband) and measured its phonon sideband, the analysis of which reveals a Huang-Rhys factor of S = 2.85 and a Debye-Waller factor of 5.8 %. The low temperature spin-lattice relaxation time was found to be exceptionally long (T 1 = 17 s at 4 K). All these properties make NV in 3C-SiC a strong competitor for qubit application. In addition, the strong variation of the zero-field splitting in the range of 4K to 380K allows its application for nanoscale thermal sensing.