International Congress on Energy Fluxes and Radiation Effects (EFRE)

Superluminescence of NV centers in diamond pumped by the second harmonic of a Nd:YAG laser

D. E. Genin, V. P. Mironov, Evgeny N. Telminov, Mikhail A. Shulepov

Published Nov 14, 2022• 0 citations

Abstract

In the light of the creation of a diamond laser [1], an urgent task is to determine the characteristics of diamonds in order to determine the range in which such lasers can be created not in isolated cases. This work is aimed at studying the mechanisms of creating superluminescence in diamond under the action of optical pumping by the second harmonic of an ND:YAG laser (λ = 532 nm). It was found that, upon pulsed excitation of a diamond by an ND:YAG laser with a pump intensity above ~2.0 MW/cm2 in the spectral range 700–750 nm, a nonlinear increase in intensity appears against the background of the spontaneous photoluminescence spectrum, which, with a further increase in the pump intensity, turns into a pronounced superluminescence peak with a maximum at about 718 nm. An increase in the pump intensity from 2.7 to 46 MW/cm2leads to the broadening of this peak at half maximum from 13 to 19 nm. At high levels of pump intensity, nonlinear absorption of pump radiation and accumulation of NV centers in the excited state were found. The position of the photoluminescence band was calculated as a function of various values of the inversion density of the populations of color centers, taking into account the intrinsic absorption spectrum of diamond. The calculation results are close to the experimental data.

DOI: 10.56761/efre2022.n4-o-011202

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