Synthesis of single-crystal low-loss LiB₃O₅ nanowire and its optical properties

Optical-quality single-crystal LiB₃O₅ (LBO) nanowires are synthesized for the first time using a sol-gel method. The LBO nanowires possess diameters ranging from 200 to 800 nm and lengths of up to 200 μm, and exhibit excellent uniformity, smooth surfaces, and good mechanical properties. A typical propagating loss of 0.038 dB/μm at 532 nm is obtained for a 620 nm-diameter nanowire. This is a decrease of one order of magnitude compared with that of a β-BaB₂O₄ (BBO) nanowire with similar diameter, which makes the LBO nanowire a promising candidate to construct miniaturized nonlinear photonic devices.