Improving the world one wavelength at a time

1 February 2017

Physics PhD student Atiyeh Zarifi in the lab. Credit: University of Sydney.
Physics PhD student Atiyeh Zarifi in the lab. Credit: University of Sydney.

Photonics is becoming more important in improving technologies, medicine and exploring the universe. The backbone of this research field is insights into the micro-structure of materials. PhD student Atiyeh Zarifi explains.

In my research, I study the interaction between the light and sound in tiny waveguides, 1000 times smaller than the human hair. Similar to their electronics chip counterparts, which guide electrons, these waveguides - called photonic integrated circuits (PICs) - are used to guide light.

Photonics is the science of light and in particular the technology of generating, controlling, and detecting light waves. The characteristics of these optical waves can be used to explore the universe, cure diseases, and even to solve crimes. The 21st century will depend as much on photonics as the 20th century depended on electronics.

In CUDOS (Centre for Ultrahigh bandwidth Devices for Optical Systems), we are working on optical science and photonics technology to bring significant advancement in the capabilities in this crucial field.

"Photonics micro-structures are the backbone of future photonics industry."

What happens when the light and sound interact in a waveguide? A high intensity light wave, creates periodic patterns of high and low densities in the waveguide-a density wave or in other words a sound wave.

The two waves -light and sound- interfere with each other and generate a third, optical wave in a new frequency. This process is called stimulated Brillouin scattering (SBS). The third, optical wave, is sensitive to the material's physical characteristics including its temperature, applied strain and inhomogeneity, which makes SBS an excellent candidate for making strain and temperature sensors.

In our research lab, I scanned a photonic integrated circuit (PIC) using SBS and created a map of the waveguide which shows how uniform this waveguide is in terms of waveguide's dimensions and fabrication errors.

Furthermore, we can detect if there is any temperature or strain variation along the waveguide. The fact that we can go down to this very fine scale in terms of sensing, gives us exciting opportunities to expand our knowledge about photonics micro-structures which are the backbone of future photonics industry. The same principal can be applied for sensing tiny vibrations in critical metropolitan structures such as bridges and high rises. Gaining those insights could allow us to make those buildings more stable in the future or to even improve their current structure.

While my research is obviously very intensive, I have had many wonderful opportunities while studying at the University of Sydney. I have had the opportunity to travel to Brazil and attend the summer school of advanced science and nano-photonics in Sao Paulo, which was a very unique experience. I am also the vice president of our optic student chapter at University of Sydney, where we have lots of events and activities including running high school visits and outreach programs to better inform the public and young students about our work and the possibilities it holds. And finally I enjoy singing in the Sydney University Student Choir and participating in concerts. The PhD life is full of discoveries and fun activities!

CUDOS is a partner in the NSW Smart Sensing Network.

Contact: Silke Weiss

Phone: +61 2 9351 2637

Email: 1431192d3067252d5f1b400938562c07344c66500530462d1a