Creating innovative microchip technologies advancing photonics, fluidics and biomedical research.
Distinguished Professor - Photonics and Electromagnetics; RMIT Node Director, Centre for Ultra High Bandwidth Devices for Optical Systems (CUDOS)
Integrated optics and photonics, photonic signal processing and Lab-on-a-Chip technologies utilising microfluidics, microfabrication and microsystems.
Professor Mitchell deliberately places himself at the boundaries between disciplines to maximise his new discoveries and the impact of his research. He is focussed on anticipating and creating future platforms that will be required by fundamental researchers three to five years into the future.
Professor Mitchell’s research is dedicated to the creation of microtechnology solutions enabled by fundamental research in diverse disciplines spanning physics, chemistry and biomedical sciences.
His early work on the simulation and design of highly integrated optics systems in collaboration with the Australian Photonics CRC and the Defence Science and Technology Organisation led to the creation of photonic signal transport and processing devices. This partnership provided him with a solid grounding in technology development and commercialisation and ultimately led to the creation of two patents and licensed technology for commercialisation.
"I am keenly aware of the need for the technologies created in Australia to be commercialised in Australia and so focus on technologies that can be scaled up for manufacturing, thus ensuring my creations are of benefit to the end user."
In addition to creating ultrafast photonic signal processing systems, Professor Mitchell conducted research into microplatform technologies such as low-cost integrated optics and microfluidic lab-on-a-chip platforms.
This expertise led Professor Mitchell to co-engineer a microfluidic device designed as a medical diagnostic tool to predict excessive or ineffective blood clotting. This device allows researchers to replicate the behaviour of blood as it clots near an injury site. By revealing a new connection between disturbed blood flow and blood clotting, this platform has helped researchers understand why anti-clotting drugs do not always work and gives scientists new targets for therapeutic treatments.
These findings were published in the prestigious Nature Medicine journal.
In 2011, Professor Mitchell's research expertise was recognised in his appointment as the RMIT Node Director of the Centre for Ultrahigh bandwidth Devices for Optical Systems (CUDOS), a Centre under the Australian Research Council's Centres of Excellence Program.
"The Centre brings together a potent team of researchers in optical science and photonics technology dedicated to developing science and engineering to transform photonic integrated circuits into a practical, powerful technology.
The technology employs optical signal processing to enable critical applications spanning communications, sensing and security," he says.
"We live in an information-rich world. The technology that makes this possible is the high speed internet and what makes the internet possible is photonics – light in optical fibres and lasers. This remarkable technology allows us to transmit and process vast amounts of information whilst consuming far less power.
In addition, photonics can interrogate molecular structures and provide information critical to human health and environmental sustainability; quantum properties of photons also promise new information systems with impenetrable security."
Continuing to focus on end users, the CUDOS RMIT node has successfully created a suite of silicon photonic design tools now licensed to Luceda Photonics, the company providing an industry standard framework for silicon photonic chip design across the globe.
Silicon photonics allows the economical production of optical devices using standard semiconductor fabrication techniques, integrated with microelectronic chips. Professor Mitchell’s team are contributing to this emerging billion dollar industry through their invention and development of new silicon photonic resonator technology designed to integrate silicon photonic transmit/receive modules, which are critically important for high speed, low-cost information transport within data centres.
Waveguide resonators are among the most crucial building blocks for silicon photonic systems and Professor Mitchell is involved in a project to introduce an entirely new class of optical waveguide resonators based on recently discovered unusual coupling behaviour in silicon photonics. The research indicates that these new compact resonant structures will offer unprecedented filtering functionality while remaining compatible with silicon photonic mass manufacture, ensuring they can be easily utilised by the broader community.
Professor Mitchell believes that being based at RMIT has enabled his research team to quickly reach their level of international expertise.
"RMIT has invested in significant infrastructure such as the Microelectronics and Materials Technology Centre and the MicroNano Research Facility, which feature all the tools required to design, fabricate, test, package and validate photonic chips and microfluidic biodevices.
RMIT has a unique and exciting emerging research culture with its broad diversity of students and collaborators creating an extremely engaging dynamic."