Photoluminescence studies of 515.8 nm, 533.5 nm and 580 nm centres in electron irradiated type IIa diamond

A series of irradiations has been performed mainly on some very high purity CVD single crystal diamonds but also on some other diamond specimens at various electron doses and dose rates. The electron energies were sufficient to cause atomic displacements creating vacancies and self-interstitials in the irradiated samples. The 515.8 nm, 533.5 nm and 580 nm centres were commonly observed in low temperature photoluminescence examination of electron-irradiated type IIa diamonds. Details of their spectra indicate that they are all related to interstitial complexes.

► Three optical centres were commonly observed in electron-irradiated IIa diamond. ► Each of them has associated high-energy LVMs and we have measured their energies. ► The results showed that these centres arise from several C-interstitial complexes. ► The LVM of one centre coincides with that calculated for tetracarbon interstitials.