Christophe Caloz

Christophe Caloz

Polytechnique Montréal and KU Leuven, Canada and Belgium

For pioneering contributions to electromagnetic metamaterials and sustained leadership in bridging the gap between microwave and photonics technologies

Christophe Caloz has a unique perspective on scientific research. He has always had an “interest in everything. Already as a teenager, [he] was as much interested in literature [and] philosophy, as science and mathematics.” For Christophe, all of these things are connected, and to make a distinction between them is a fallacy. “If you really do cutting-edge research, as we all hope to do, you are after inspiration, and scientific and artistic inspirations are essentially the same process.”

Christophe comments that many scientists are “one-sided,” and often stay within their specific topics for their whole careers. For him, developing a multi-faceted perspective of things is central to research creativity. The emphasis on the unification of the artistic and scientific sides of the brain drives his work, and he comments, “if I had only one, I would feel like a tennis man with a huge right arm. In a match, I would probably feel the missing left arm.” This idea applies to all professions when pushed beyond usual limits. The two sides need to balance: “And then when you have this, you can approach your scientific research with a kind of artistic creativity. And perhaps, when you do something more artistic or literary, then you have a kind of rigor of strengths that allows you to have a powerful message that you might not have otherwise.”

In working toward this balance, Christophe found himself in the midst of a challenge when he first entered into science. Previously, he had focused on the “classics” and learned Latin, literature, and philosophy. It wasn’t until he was around 19 years old that he realized he could do those things as a hobby, and said to himself “You’ve got to learn something practical like being a surgeon or…an engineer.” He knew then that he would have to switch educational paths. The challenge? He didn’t have a specific science background at that point. He turned to his professors, past and present, for guidance. One told him, “if you go through a [challenging time]…and then you [succeed], you get a special momentum. This momentum then brings you farther than the others.” Christophe reflects that there were only two possibilities at that time: “you crack and you go into a depression, or you…[succeed] and fly like a charm,” so he worked hard and succeeded.

Today his research falls under the umbrella of metamaterials. In this field, Christophe’s work covers the two areas of magnetless nonreciprocity and spacetime metamaterials. Always calibrating his explanation to his audience, Christophe was able to explain the former in terms anyone could understand: “You know reciprocity: ‘I pay you a drink, you pay me a drink.’ This is reciprocal. Nonreciprocity is: ‘I pay you a drink and you do not pay me a drink.’ So, it goes only one way. This is not nice in relationships, but in engineering this is very useful.” At a very basic level, this work revolves around creating new nonreciprocal materials that are compatible with integrated-circuit technology present in nearly all modern-day electronics, and hence inexpensive and effective. He works to combine the technology of metamaterials and metasurfaces into something that may soon be “revolutionary.” The other part of Christophe’s work covers spacetime metamaterials. In this area, Christophe is developing materials that are modulated in both space and time in a systematic way. Again, tailoring to his audience, he explains, “If you want to meet [someone] you have to be in the right point in spacetime. It is not enough to go to the right pub. You have to go to the right pub at the right time…So it’s about…manipulating matter in both space and time.” The passion and dedication Christophe conveys about his work is undeniable.

At many times throughout the interview, Christophe brought up the idea of two opposing sides working together: left brain and right brain, yin and yang, hard and soft sciences, Nietzsche’s Apollonian and Dionysian. Perhaps the most inspiring of all was his discussion of pessimism versus optimism. “When I was a postdoc I realized that in science there were two possible perspectives: the pessimistic and the optimistic….The pessimistic perspective consists in saying ‘so many things have been done by so many smart people that it is almost impossible to make your own mark.’ This vision can be very well argued. The optimistic approach would be to say, ‘But there have been so many things being established that the possibilities of combinations have grown dramatically.’ So, the opportunities are greater than ever, and that can also be sustained.” The vast amount of discoveries has only opened doors for contemporary scientists, and there is no limit. While the reality of things may be in between these two sides, it certainly brings more to look at the optimistic side. He quotes Robert Goddard, “’The dream of yesterday is the hope of today  and the reality of tomorrow.’…If you don’t have a big dream, nothing significant occurs.”

Once you have a dream, what advice would Christophe offer? He starts with what is, according to him, a myth of education, or the idea presented in many classrooms that complex topics should be easily understood. In reality, most of the concepts that are presented in textbooks took years of trial and error to develop, and students should not feel embarrassed or depressed if they don’t understand right away. Christophe even suggests that many professors only have a superficial understanding of the concepts. He urges students: “Don’t be intimidated by the complexity of things.” Christophe further stresses the importance of understanding, not just knowing: “[If you don’t spend the time to really understand things], at the end of the year, in the end when you become a professor, your mind is full of holes…like Swiss cheese. But if along the way…you spend the time to fix [it]…then you establish a way of thinking that allows you to tackle any possible problem.” Christophe closes with, “What matters is not to know, but it is to be able to understand… and innovate.”

Photo Credit: Christophe Caloz

Profile written by Samantha Hornback