CAPPA is involved in the advanced research of nanophotonics through the nanophotonics group at CAPPA. The nanophotonics group uses nanoscale devices (smaller than a hair’s width) to control and manipulate light. By nanostructuring high refractive index silicon based materials, light can be confined in volumes on the order of a cubic wavelength. A particular goal of the group is the demonstration of a low power consumption optical interconnects based on low capacitance photonic crystal cavities that are compatible with the fabrication process of the electronics industry. The group’s main research goal is the realisation of a new family of low power optical interconnects using Nanophotonics.
Recent Research Highlights
Nanophotonics article on “High-Q asymmetrically cladded silicon nitride 1D photonic crystals cavities and hybrid external cavity lasers for sensing in air and liquids.”
In the paper we show a novel design of high Q-factor silicon nitride (SiN) 1D photonic crystal (PhC) cavities side-coupled to curved waveguides, operating with both silica and air cladding. The engineering of the etched 1D PhC cavity sidewalls angle allows for high Q-factors over a wide range of upper cladding compositions, and the achievement of the highest calculated Q-factor for non-suspended asymmetric SiN PhC structures. We show the employment of these type of SiN PhC cavities in hybrid external cavity laser (HECL) configuration, with mode-hop free single mode laser operation over a broad range of injected currents (from 25 mA to 65 mA), milliwatts of power output (up to 9 mW) and side-mode suppression ratios in the range of 40 dB.
See the full paper here: Iadanza, Simone, Mendoza-Castro, Jesus Hernan, Oliveira, Taynara, Butler, Sharon M., Tedesco, Alessio, Giannino, Giuseppe, Lendl, Bernhard, Grande, Marco and O’Faolain, Liam. “High-Q asymmetrically cladded silicon nitride 1D photonic crystals cavities and hybrid external cavity lasers for sensing in air and liquids” Nanophotonics, vol. 11, no. 18, 2022, pp. 4183-4196.
CAPPA has access to the cleanroom facilities at Tyndall through the CAPPA@Tyndall partnership. Tyndall central fabrication facilities consist of three distinct cleanroom spaces; 250m² of class 1,000 and class 10 for silicon fabrication, 750m² of class 10,000 and class 100 for MEMS and compound semiconductor fabrication and 40m² of class 1000 for e-beam lithography. Tyndall’s flexible fabrication offering – FlexiFab, is in a unique position to allow for greater material exchange between the fabrication areas, whilst maintaining protocols to avoid cross contamination.