Luminescence of brown CVD diamond: 468 nm luminescence center

Abstract

Detailed study of the luminescence of multiple brown CVD diamonds was performed. It has been found that the well-known optical center with zero-phonon line at 468 nm is a characteristic of brown color. It has been found that the defects responsible for 468 nm center are located within brown striations suggesting close relation of the 468 nm center and the vacancy clusters. Simultaneous reduction of the intensity of 468 nm center and brown color during annealing support the assumption of their close relation. Identical spectroscopic parameters of the 468 nm center and the radiation center with ZPL at 492 nm suggest that the former relates to an intrinsic defect probably containing vacancies. The distribution of intensity of the 468 nm center in some brown diamonds follows the distribution of the NV − center while being opposite to that of the NV 0 center and the dislocation-related A-band. This observation suggests the negative charge state of the 468 nm center. Due to its high luminescence efficiency, the 468 nm center can be used as a highly sensitive indicator of the traces of vacancy clusters. We found that the 468 nm center is detected practically in every as-grown CVD diamond including colorless CVD diamonds of high structural perfection and high purity.

Enhancement of the creation yield of NV ensembles in a chemically vapour deposited diamond

“…The different stacked layers can be clearly distinguished as they exhibit pink to dark colour from the lowest to highest doping levels. This colour is noteworthy as growth on [100]-oriented diamonds with high nitrogen doping is more likely to lead to a brown colouration originating from a large amount of absorbing defects such as aggregated vacancies [36]. This is already a first hint that NV centres are a dominating impurity in our case which would support our previous statement.…”

Raman Study of the Diamond to Graphite Transition Induced by the Single Femtosecond Laser Pulse on the (111) Face

“…The nitrogen concentration in the sample did not exceed 10 17 cm −3 and measured photoluminescence spectra did not contain any impurity–defect band. The only noticeable line with a maximum at 492 nm [ 24 ] and FWHM of ~3.5 nm had an intensity 5000 times lower than the Raman diamond peak (see Supplementary Materials ).…”

Synthesis of Diamonds and Their Identification

“…CVD-specific PL features include peaks at 468 nm (also reported at 467 nm) and 533 nm (or 534 nm), and a doublet at 596/597 nm. The center responsible for the 468 nm peak (also referred to as TR12') may involve nitrogen as the peak's intensity increases with nitrogen concentration, but has also been attributed to interstitial-or vacancy-clusterrelated defects (Iakoubovskii and Adriaenssens 2000a,b;Iakoubovskii et al 2000;Rzepka et al 2001;Zaitsev 2001;Iakoubovskii and Stesmans 2002;Zaitsev et al 2021). The 533 nm peak may originate from a nitrogen-vacancy type complex (Ruan et al 1991;Zaitsev 2001).…”

“…HPHT annealing destroys the defects responsible for the 389, 468, 533, and 596/597 nm features, while also reducing the intensity of NV centers (Charles et al 2004;Martineau et al 2004;Wang et al 2012;Zaitsev et al 2021). Yet these conditions result in the formation of more complex nitrogen-related defects such as N3 (N 3 V 0 , 415 nm), H3 (N 2 V 0 , 503.2 nm), and its negatively charged counterpart, H2 (986 nm).…”