In the current study, the effect of superalkalis (Li3O, Na3O, and K3O) doping over bowl shaped silicon carbide (b-SiC) for geometrical, electronic and nonlinear properties has been investigated using DFT theory. The results revealed that doped b-SiC nanoclusters possess high thermodynamic stability as revealed from interaction energy up to −165.85 kcal/mol. The frontier molecular orbitals illustrate the occupation of electronic density in orbitals. Natural bond orbital charge analysis confirms the charge transfer from superalkalis to the b-SiC nanocluster. Furthermore, the electronic properties are rationalized from total density of states spectra. The highest first hyperpolarizability value (5979.99 au) is observed for isomer O of K3O@b-SiC complexes. The electronic excitation is analyzed through UV–VIS analysis. Two-level model describing the internal factors responsible for enhancement of NLO response is also studied. The present work gives a guideline for the synthesis of nonlinear optical materials with greater efficiencies which can be used as building blocks in the modern world of optoelectronics.