University of Arkansas gets $250k to develop microwave photonics platform
Sapphire-based technology could potentially replace silicon-photonics for datacom and harsh environments
The US National Science Foundation has given a grant of just over $250,000 to two professors at the University of Arkansas to develop a new Integrated Microwave Photonics (IMWP) chip.
The two year project, 'EAGER: Sapphire Based Integrated Microwave Photonics' will be headed by Samir El-Ghazaly and Shui-Qing Yu who will use R-plane Sapphire technology to build a platform to meets future demands for improvements in performance and efficiency.
The proposed approach enables the integration of complete sets of microwave and optical components such as light sources, analogue and digital signal processing circuits, light detectors, control circuits, and Silicon on Sapphire (SOS) radio-frequency (RF) circuits all-in-one sapphire platform to achieve high-performance and low-cost mixed-signal optical links.
Sapphire has a lower refractive index with an index difference of 0.3 with Si3N4. Therefore, it could leverage the mature Si3N4 low-loss waveguide technology to produce similar low-loss waveguide-based passive components by drop-in replacing quartz wafers with sapphire wafers.
For RF applications, the sapphire platform has a potential to obtain much higher dynamic range due to low-loss optical waveguides while the competing Si-photonics platform combined with off-chip 1.55 micron laser suffers from the strong two-photon absorption and therefore has a limited dynamic range.
As a transparent substrate, sapphire would enable a versatile 3-D photonics/electronics integration architecture.
This project aims to, first, study the feasibility of the proposed approach by identifying and investigating key fundamental challenges, then, conduct a proof-of-concept study to provide an effective route for overcoming the identified obstacles, and, eventually, provide a conclusive recommendation as to whether the proposed research is feasible.
As a fully integrated solution to fundamentally address the most important technical challenge in IMWP, if successful, the new platform would find applications in defence systems, such as radar signal processing, and many civilian applications. The broad wavelength coverage enables on-chip sensing applications. It could potentially replace the current silicon-photonics for datacom and be used in harsh environments such as space and nuclear applications.
