Quantum topological photonics with special focus on waveguide systems

In the burgeoning field of quantum topological photonics, waveguide systems play a crucial role. This perspective delves into the intricate interplay between photonic waveguides and topological phenomena, underscoring the theoretical underpinnings of topological insulators and their photonic manifestations. We highlight key milestones and breakthroughs in topological photonics using waveguide systems, alongside an in-depth analysis of their fabrication techniques and tunability. The discussion includes the technological advancements and challenges, limitations of current methods, and potential strategies for improvement. This perspective also examines the quantum states of light in topological waveguides, where the confluence of topology and quantum optics promises robust avenues for quantum communication and computing. Concluding with a forward-looking view, we aim to inspire new research and innovation in quantum topological photonics, highlighting its potential for the next generation of photonic technologies.