Direct formation of nitrogen-vacancy centers in nitrogen doped diamond along the trajectories of swift heavy ions

We report depth-resolved photoluminescence measurements of nitrogen-vacancy (NV−) centers formed alongthe tracks of swift heavy ions in type Ib synthetic single crystal diamonds that had been doped with 100 ppm nitrogen during crystal growth. Analysis of the spectra shows that NV−centers are formed in regions where electronic stopping processes dominate and not at the end of the ion range where elastic collisions lead to formation of vacancies. Thermal annealing further increases NV yields afterirradiation with SHI preferentially in regions with high vacancy densities. NV centers formed along the tracksof single swift heavy ions can be isolated with lift-out techniques for explorations of color center qubits inquasi 1D registers with average qubit spacing of a few nm and of order 100 color centers per micron along 10 to 30 micron long percolation chains.