Abstract: Optical quantum chips based on coupled waveguide systems achieve quantum functionality through photon transport and inter-waveguide coupling, offering strong scalability and serving as a vital platform for optical quantum information processing. Three-dimensional optical quantum chips fabricated by femtosecond laser direct writing possess more flexible 3D configurations compared to traditional planar chips to bring forth enhanced functions including optical communication, quantum computing, all-optical logic operations, and on-chip information processing. Moreover, the propagation equation of light in coupled waveguide systems closely resembles the Schrödinger equation that governs the dynamics of microscopic particles. This similarity enables the use of optical quantum chips to simulate complex condensed matter quantum phenomena that are challenging to observe directly. Consequently, optical quantum chips not only have diverse applications but also serve as a powerful platform for studying cutting-edge physics concepts like topological physics and non-Hermitian effects. Currently, three-dimensional optical quantum chips, with their unique technological advantages and extensive application prospects, have become one of the key directions for future chip development. They open new avenues for maintaining global technological leadership, significantly bolstering China's prominence in advanced technology sectors.

Key words: Three-dimensional Photonic Quantum Chip, Femtosecond Laser Direct Writing, Optical Simulation, Integrated Photonic Quantum Computation, Topological Photonic Quantum Chip