Determination of temperature dependent parameters of zero-phonon line in photo-luminescence spectrum of silicon-vacancy centre in CVD diamond thin films

In this work we present a methodological approach to the temperature dependence of photoluminescence (PL) emission spectra of the silicon-vacancy centre in diamond thin films prepared by chemical vapour deposition. The PL spectra were measured in the temperature range of 11 - 300 K and used to determine the temperature dependence of the zero-phononline full-width at half-maximum and of the peak position. Experimental data were fitted by models of lattice contraction, quadratic electron-phonon coupling, homogeneous and inhomogeneous broadening. We found that the shift of peak position and peak broadening reflect polynomial dependence on temperature. Moreover, a proper setting of monochromator slits width is discussed with respect to line profile broadening.