Photonic crystal surface-emitting lasers (PCSELs) leverage two-dimensional photonic crystals to modulate the in-plane optical field, enabling large-area coherent oscillation. These lasers offer distinct advantages, including single-mode operation, high output power, exceptional brightness, and minimal beam divergence angles, positioning them as a focal point in contemporary research. Gallium nitride (GaN)-based semiconductor materials, characterized by their direct bandgap properties, exhibit an emission wavelength spectrum spanning from visible light to deep ultraviolet. Coupled with their high luminous efficiency and chemical stability, these materials are ideally suited for PCSEL fabrication. GaN-based PCSELs demonstrate immense potential for applications in cutting-edge displays, additive manufacturing, underwater and inter-satellite communications, chip-scale atomic clocks, deep-space exploration, and laser-based medical treatments, garnering significant interest from the scientific and industrial communities.