title: Diffuse reflection inside a hexagonal nanocavity.
abstract: Geometrical diffuse reflection is a common optical phenomenon that occurs when a reflecting surface has roughness of order of hundreds of micrometres. Light rays thus reflect uniformly in all directions with each ray obeying Snell's law. Of interest is knowing what happens when light reflects off surfaces with roughness of nanometres. Here, by introducing nanoscaled roughness on the hexagonal faces of ZnO nanocavities, we observe luminescent profiles with flowery patterns, replacing the usual whispering gallery modes. The unique profile for these nanocavities is attributed to wave diffuse reflection, which occurs when the features on the reflecting surfaces are typically nanometre-sized. Light with wavelengths of similar scale "sees" these nano-perturbations, and undergoes scattering rather than geometrical diffuse reflection. These findings could benefit the fields of nanoscale topography and nanoscopic uniform lighting by using wave diffuse reflection.
authors: State Key Laboratory of Optoelectronic Materials and Technologies, Institute of Optoelectronic and Functional Composite Materials, School of Physics & Engineering, Sun Yat-sen University, Guangzhou, Guangdong, P R China.
authors: Nengwen
authors: N
authors: Wang
authors: Xiaodong
authors: X
authors: Chen
authors: Yuhua
authors: Y
authors: Yang
authors: Jianwen
authors: J
authors: Dong
authors: Chengxin
authors: C
authors: Wang
authors: Guowei
authors: G
authors: Yang