Effect of electron-beam irradiation on the luminescent properties of nitrogen-related defects in the needle shaped diamond

Nitrogen-containing structural defects in diamond that exhibit luminescent properties are highly attractive for quantum sensing and information processing. Controlling the formation and modification of these defects, especially ensuring their localization, is an important challenge. In this study, we investigate the local effects of electron-beam irradiation on the luminescent characteristics of single-crystal diamond in the form of needle-like crystallites. These diamond needles were grown using chemical vapor deposition (CVD) as part of polycrystalline films and were subsequently extracted by gasifying the more defective parts of the films during thermal oxidation. The needles, with lengths exceeding 100 μm and thicknesses up to 10 μm, were irradiated with a focused electron beam at accelerating voltages ranging from 5 to 30 kV. Cathodoluminescence (CL) and photoluminescence (PL) mapping revealed a pronounced local decrease in the intensity of the 389 nm CL band, accompanied by increases in the intensities of the 575 nm and 634 nm PL bands in the irradiated regions. This effect is attributed to the transformation of nitrogen-related defects present in the as-grown diamond needles into specific forms—namely, NV 0 and NV − centers. The obtained results demonstrate a method for localized control of nitrogen-vacancy centers and may also be significant for interpreting experimental data in studies related to nitrogen defects and luminescent centers in diamond. • Electron beam irradiation modifies photo- and cathode-luminescent spectral and intensity mapping for single crystal diamond needles; • e-beam irradiation with energies of 5 to 30 keV and currents of 10 to 100 nA transform N-related defects in diamond into NV0 and NV luminescent centers; • Obtained results indicate on possibility for local change of NV centers concentration by using common SEM instrumentation.