“I teach a subject that's notoriously hard to learn”

When he was a student, Romain Fleury feared the subject he now teaches at EPFL. “I teach something that’s notoriously hard to learn. When someone first tried to explain electromagnetics to me, I didn’t understand a thing. It was way too complicated,” he says. And it’s true that the subject is a perfect storm of highly abstract concepts and convoluted equations. So when he started teaching, Fleury spent a lot of time figuring out how he could clearly explain the inner workings of electrical signals and the propagation of electromagnetic waves. These waves can be found just about everywhere – from telecommunications networks and acoustics systems to medical imagining machines – but are understood by only a select few.

Upon joining EPFL in 2017, Fleury completely revamped the two electromagnetics classes he was asked to give to Bachelor’s students in electrical engineering. And apparently he hit on a winning formula, because this year, in addition to being named best teacher in his section, he also won a Polysphère award. That shows he is appreciated by his students and colleagues alike. “I’ve invested so many hours preparing my classes and that it’s nice to be recognized,” he says. “As professors, we have a responsibility to impart our knowledge to the next generation. Teaching also helps us stay abreast of the latest developments in our field and feel useful. In research, you can have good and bad days, and there are times you feel frustrated or even defeated if your experiments don’t go as expected. You don’t get that in teaching.”

Fleury, who views his lectures as “public speeches,” is consistently impressed by his students’ curiosity. “I didn’t get very good evaluations the first year I taught because my classes were too easy. So I spoke with some colleagues at MIT and Stanford, and the following year I aligned my course content with theirs. And my students were really happy. Sometimes you have to be willing to risk going further, digging deeper, to quench students’ thirst for knowledge,” he says.

Depicting the invisible

To capture his students’ attention and give them the building blocks they need to fully understand the concepts of electromagnetics, Fleury starts by walking them through the history of the technology. He shows them the bulky telegraph cables that engineers first used, and describes how England initially dominated the cable-production industry by sourcing rubber from its colonies in India. He also takes students step by step through the equations used in the process, giving concrete examples of how they got more complicated as electromagnetic waves replaced telegraph cables.For example, he asks students why submarines need to go up to the sea surface to communicate, while in a lake they can stay at the bottom or why thin, high-index lenses allow more light to pass through.

And for the lab sessions, Fleury has his first-year students study a very popular musical instrument: the ukulele. “They have to work in groups and make measurements to determine how the sound is created and describe the resonant properties of its sound board,” he says. That helps students better grasp the abstract concepts. He adds, “I’ve always viewed science as something tangible and not purely mathematical.”

Fleury probably inherited his passion for engineering from his grandfather, who worked as an engineer for Renault. When Fleury was a boy, his grandfather frequently showed him the various things he had cobbled together. “I remember once he showed me a dodecahedron that he’d made from a sheet of paper. I have great memories of this time together, and that probably played a role in my choice to study electrical engineering,” says Fleury. And now that he himself is a father – of three children, aged six, four, and eighteen months – he regularly conducts fun, informative experiments with his older kids. And he has material to draw on: he is currently working on developing synthetic materials with a negative refraction index that could be used to make objects invisible or to create WiFi-free areas. However, his oldest son was disappointed to see that the cloak of invisibility being concocted in Fleury’s lab doesn’t (yet) look like Harry Potter’s.