Photonic Crystals

Blog vol II. 29, Photonic Crystals



A photonic crystal is a periodic optical nanostructure that affects the motion of photons in much the same way that ionic lattices affect electrons in solids. Wikipedia


What is that? Sounds like something out of Sci-Fi. The idea actually comes to us from nature in the form of iridescent butterfly or dragonfly wings or from minerals like opals. The colours will shift on the object because of these nanostructures, depending on the angle of viewing. 

This week we congratulate Dr. Sajeev John and his team at U of T for being awarded the 2021 $1 Million Herzberg Medal for their ground-breaking research with light.


For the past century many scientists have worked on unlocking the secrets of these crystals. Interestingly, we have been using PC’s in industry and science for some time, without even realizing it. 


The multi- layer anti-reflection coatings that we have on our optical lenses are a form of one dimensional photonic crystal. 


The fibre optic cables that we use for lasers and for transmitting data are a complex form of two dimensional photonic crystal.  


Recent advances in engineering have made it possible to create these photonic crystals in three dimensions, making it possible to precisely manipulate the flow of light for medical laser applications, for advanced computers, and for solar cell technology.


Dr. John’s has been doing research in the area of light since he finished his Ph.D. at Harvard in the 80’s.  With the advance in 3D PC’s, the door has been opened to innovative solar cells. Hence the big grant money, in the hope that solar cell technology being everywhere and on everything would be a climate game changer. I want to acknowledge the ingenuity of the engineers who designed these crystals and the hard work yet to be done by them to bring them to market.


Congratulations to Dr. John and his team,

 

the good doctor, Dr. Mark Germain, Burlington Optometrist

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