Cascaded third-harmonic generation in a single two-dimensional nonlinear photonic crystal with a short-range order

Short-range ordered nonlinear photonic crystals (SRO-NPC) are new, promising class of materials for optical frequency conversion. We describe a method for designing such SRO-NPC for efficient collinear third-harmonic generation (THG) at arbitrary wavelength. The method was used to prepare a LiNbO
₃
sample in which THG at 526.7 nm with 12% efficiency was achieved.