Radiative and nonradiative recombination rates in cubic SiC

► Cubic SiC was studied by free carrier absorption and photoluminescence techniques. ► Free carrier decay kinetics supplied nonradioactive recombination coefficients. ► Experimental PL injection dependence provided radiative bimolecular coefficient. ► Injection-dependent PL spectra exhibited bandgap filling and renormalisation. ► Internal quantum efficiency was calculated, using the determined coefficients.