Improving solid to hollow core transmission for integrated ARROW waveguides

Abstract

Optical sensing platforms based on anti-resonant reflecting optical waveguides (ARROWs) with hollow cores have been used for bioanalysis and atomic spectroscopy. These integrated platforms require that hollow waveguides interface with standard solid waveguides on the substrate to couple light into and out of test media. Previous designs required light at these interfaces to pass through the anti-resonant layers. We present a new ARROW design which coats the top and sides of the hollow core with only SiO 2 , allowing for high interface transmission between solid and hollow waveguides. The improvement in interface transmission with this design is demonstrated experimentally and increases from 35% to 79%. Given these parameters, higher optical throughputs are possible using single SiO 2 coatings when hollow waveguides are shorter than 5.8 mm.

Enhancement of ARROW Photonic Device Performance via Thermal Annealing of PECVD-Based SiO2 Waveguides

“…Many recent implementations of ARROW chips rely heavily on an orthogonal excitation/collection geometry for fluorescence detection [9]. As such, optimization of these SiO 2 ridge waveguides is of paramount importance and has been extensively studied [10]–[12]. Here, we show that a distinct upper layer (DUL) with increased refractive index in the SiO 2 ridge waveguides is formed during fabrication.…”

Infrared fibers

“…This concept originates from the early studies on antiresonant reflecting optical waveguides (ARROWs) in SiO 2 -Si multilayer structures in the 1980s [426]. More studies were carried out on the guiding conditions, single-mode operation, and analysis of leakage properties of various ARROWs where the core is either a low-refractive-index material or air (hollow core) [427][428][429][430][431][432][433]. The major motivation behind these studies is the applications of these waveguides in integrated photonics, sensing, and quantum communications.…”

Integration of programmable microfluidics and on-chip fluorescence detection for biosensing applications

“…35 Liquid-core waveguides were formed on top of the layers using SU8 sacrificial layers with dimensions of 5  12 lm (height  width) using self-aligned pedestals 36 and a single layer over coating oxide with transmission optimization. 37,38 After the single 6 lm thick over coating SiO 2 film was deposited, solid-core ridge waveguides were formed using reactive ion etching. Solid-core waveguides were etched to 4 lm widths and 3 lm ridge heights (see supplementary material 29 for cross-sectional view).…”