FDTD-based design of high quality factor quantum dot photonic crystal nanolaser for next-generation nanotechnologies.

Photonic crystal cavities engineered for high-performance terahertz (THz) emission offer a promising route toward compact quantum-photonic platforms. Here, we introduce a hybrid indium phosphide/zinc oxide (InP/ZnO) quantum-dot photonic crystal laser that exploits the wide bandgap of ZnO (≈ 3.37 eV) and its highly scalable nanorod and thin-film growth modes to sustain strongly confined optical states. By systematically analyzing the quality factor under variations in temperature-dependent dispersion and radius-to-lattice constants, we demonstrate a substantial enhancement in spontaneous emission and optical pumping efficiency. Our optimized structure achieves quality factors up to 1600 for InP and further improved performance in the InP/Al₂O₃/ZnO hybrid gain medium. Finally, we route the photonic crystal laser output into quantum logic-gate architectures and quantify its angle-dependent rotation dynamics and probability distributions, highlighting its feasibility for next-generation quantum laser processing.