Optical coherence of diamond nitrogen-vacancy centers formed by ion implantation and annealing

Abstract

The advancement of quantum optical science and technology with solid-state emitters such as nitrogen-vacancy (NV) centers in diamond critically relies on the coherence of the emitters' optical transitions. A widely employed strategy to create NV centers at precisely controlled locations is nitrogen ion implantation followed by a high-temperature annealing process. We report on experimental data directly correlating the NV center optical coherence to the origin of the nitrogen atom. These studies reveal low-strain, narrow-optical-linewidth (< 500 MHz) NV centers formed from naturally-occurring 14 N atoms. In contrast, NV centers formed from implanted 15 N atoms exhibit significantly broadened optical transitions (> 1 GHz) and higher strain. The data show that the poor optical coherence of the NV centers formed from implanted nitrogen is not due to an intrinsic effect related to the diamond or isotope. These results have immediate implications for the positioning accuracy of current NV center creation protocols and point to the need to further investigate the influence of lattice damage on the coherence of NV centers from implanted ions.

Robust all-optical single-shot readout of nitrogen-vacancy centers in diamond

“…We note that sub-GHz optical linewidths have been reported for comparable implanted NV centers as shallow as 10 nm 16,17 . The protocol also promises to be resilient to high-strain environments, since it does not make use of the spin-selective intersystem crossing into the 1 A singlet state.…”

Quantum nanophotonics with group IV defects in diamond

“…Group IV defects in diamond have advantages over other solid-state emitters for these crucial aspects. Unlike NV – centres, which have poor optical linewidths when produced through ion implantation, 83 SiV – centres have been shown to have highly coherent optical transitions when incorporated in this fashion. A similarly high photon coherence has since been demonstrated for GeV – and SnV – , showing that the inversion symmetry of the diamond M-V defects makes them robust in this respect.…”

Optically Coherent Nitrogen-Vacancy Centers in Micrometer-Thin Etched Diamond Membranes

“…NV centers created from implanted nitrogen atoms were recently found to predominately feature broad optical lines, likely due to associated diamond lattice damage. 50 Instead, we use high-energy electron irradiation to create vacancies throughout the whole diamond that can form NV centers with native nitrogen (see Figure 1A). 51 After triacid cleaning, a high-temperature and high-vacuum annealing sequence, consisting of three temperature steps, ensures the recombination of vacancies with naturally occurring nitrogen in the diamond to form NV centers and anneals out vacancy chains (see Figure 1B).…”