Journal Article

Optical waveguide in curved and welded perovskite nanowires

Hong, BinBin, Wang, GuoPing, Zhang, ZhenYu, Zhang, YuPeng

2023

Overview

Single-crystalline lead halide perovskite nanowires are emerging as promising one-dimensional blocks for nanoscience and nanotechnology, and extensive studies of nano-lasers and nano-photodetectors have been reported. However, as perfect confined structures, their optical waveguide performances have not been widely paid attention to up to now. Here, we report on the such issue on single-crystalline CsPbBr 3 nanowires and quantify it by near-field optical response mappings. The waveguide is verified as total internal reflection mode at the visible band (532 nm), and its far-field end-facet coupling efficiency of 89.6% and propagation loss as low as 5.9 dB/mm are measured from the nanowire with cross-sectional geometry of ∼600 nm × 300 nm. No evident bending loss exists in naturally curved nanowires, while it usually emerges in artificial-bended ones due to the wrinkled surfaces. Naturally welded nanowire networks show significant advantages in integrated waveguides over the artificial assembled ones, due to the coupled photons at the space-confined end-facet segments. Roughened surface reasoned by lattice degradation is detrimental to propagation loss, but it provides leaked channels for waveguide coupling on nanowire surface. This work studies the optical waveguide performance of perovskite nanowires with different geometries and goes a step further for integrated nanophotonics.

• Publisher: Science China Press,Springer Nature B.V
• Subject: Coupling / Engineering / Far fields / Laser beam welding / Lead compounds / Metal halides / Nanowires / Optical waveguides / Perovskites / Single crystals