Change in Luminescent Properties of Diamond Stimulated by Subnanosecond Laser Pulses at Low Temperatures

The effect of 532-nm pulsed laser radiation on properties of a single-crystal diamond film containing optically active SiV‒ centers is studied using in-situ measurements of the photoluminescence spectra at a temperature of 77 K. It is shown that at a pulse duration of 500 ns, the threshold energy density at which the rearrangement of SiV‒ centers is recorded is ~0.112 J/cm2. The rearrangement leads to a decrease in the intensity of the zero-phonon emission line of SiV‒ centers relative to the intensity of the Raman scattering signal on optical phonons of the diamond matrix. With an increase in the energy density of incident pulses to 0.540 J/cm2, the luminescence quenching effect reaches saturation, and traces of ablation and/or graphitization are observed on the film surface. The found effects are explained by local heating of the diamond film due to the processes of three-photon absorption of light, in which the absorption coefficient sharply depends on the energy of incident pulses.