Yau Chuen Yiu's research interests are interdisciplinary, spanning optical instrumentation and materials science, with a specialisation in diamond photonics for optical anti counterfeiting and communication, deep-ultraviolet (DUV) plasmonic materials, and DUV hyperspectral micro- and nanoscopy using fluorescence and Raman scattering to investigate wide-band-gap semiconductors (e.g., boron nitride and diamond) and biological materials (nucleic acids and amino acids).