by Gwyn Moe
Thierry Lapointe-Leclerc knows that science would be nowhere without the dedication and passion of the researchers behind it.
As an Electrical and Computer Engineering PhD student in Professor Siddharth Ramachandran’s lab and as president of Photonics Student Society, he hopes his time at Boston University will leave a positive impact in the community, no matter how small.
Unlike other students, Lapointe-Leclerc’s path to STEM wasn’t an inevitability. While in high school, he didn’t initially feel connected to any science classes. Ultimately, he was drawn to the field because, “there would be this huge chunk of knowledge about the world that I’d never be able to understand, and it would bug me.”
During his undergraduate career, Lapointe-Leclerc realized his passion was not creating components for larger research projects, but applying photonics in practical ways. “I not only want to build up the basic tools of photonics but also to use them to positively impact people’s lives.” This focus on application is one of the reasons he wanted to be a part of Professor Ramachandran’s research at Boston University.
“By using the tools of Photonics at our disposal… we hope to achieve strong performance on complex problems with higher efficiency than equivalent electronics.”
However, choosing BU wasn’t just about the research opportunities but also about the resources made accessible by the Photonics Center. “I couldn’t imagine just doing photonics in a bubble with only one group and no resources,” Lapointe-Leclerc says.
As an international student from Canada, Lapointe-Leclerc’s path to the Ramachandran Lab was also unconventional. Most PhD candidates at Boston University apply to a program or department and spend their first year taking classes and rotating between two or three different labs, before ultimately joining the one in which they will complete the remainder of their program. Lapointe-Leclerc, on the other hand, applied directly into Professor Ramachandran’s lab––something common internationally, but not in the United States.
Professor Ramachandran’s lab focuses on a few different research topics, but Lapointe-Leclerc’s work lies in the field of nonlinear and quantum photonics.
Nonlinear phenomena is how we get photons to interact with each other. This creates a system in which the output is not merely a weighted linear combination of the inputs but something more complicated. This manifests itself in the specific combination of output wavelengths (or colors) and, in our case, modes, being different from those you put in. In this way, you can encode information at the input and measure the computations on that input, performed through the mere act of propagating through a nonlinear medium, at the output
In the lab, Lapointe-Leclerc uses optics to improve the capabilities of machine learning. “By using the tools of photonics at our disposal, such as being able to send a lot of information at once and performing through simple propagation in our nonlinear fibers,” he explains, “we hope to achieve strong performance on complex problems (or tasks) with higher efficiency than equivalent electronics.”
By leveraging optics, the Ramachandran lab can optimize machine learning systems. Lapointe-Leclerc describes how, by using beams with high orbital angular momentum, they can minimize cross talk between multiple channels. This ensures that each mode is able to operate independently without mixing in the linear regime. “If you do a good job of exciting exactly the mode that you want, it’s almost as if it [the mode] doesn’t see the other modes.”
The level of control that’s able to be achieved over the amount of linear mixing, is the differentiator between what the Ramachandran lab is trying to accomplish and what’s already out in the world. “My goal is to use our modes, over which we do control the linear aspect, to do what’s been done in that field, but with an extra degree that we can decide to tailor,” says Lapointe-Leclerc.
If this research proves successful, it could be utilized to improve high-speed data processing, real-time image or video analysis, fast image classification—of, for example, medical scans—high-speed sensing, and generally faster and more efficient computing for large problems.
“The question is, how do you create a sense of community [where] we can all learn together?”
Alongside improving data interaction, Lapointe-Leclerc also hopes to make the Photonics community a more interactive environment. When he arrived at Boston University in 2023, he immediately noticed how difficult it was for students to connect with each other, especially coming off of the COVID-19 pandemic. “You really don’t come across each other, except maybe at the elevators,” he says, and goes on to explain that even then, Photonics students are spread out between multiple buildings, not just the Photonics Center.
As president of the Photonics Student Society, he’s working to bridge that gap. “The question is, how do you create a sense of community [where] we can all learn together?”
There are many components to the work the society does. “There’s outreach, there’s organizing socials, organizing scientific talks, educational events, networking events, promoting different issues that might need promotion or visibility,” Lapointe-Leclerc explains. They work hand-in-hand with the Photonics Center, funding organizations, and other student clubs, to put together events and share information.
The society has gone through many changes in the past few years––name changes, new leadership elections, and even a temporary shut down due to the pandemic. Because of this, there’s still a lot of rebuilding to be done, but Lapointe-Leclerc is confident that if they are consistent, there will be an impact.
One of the society’s most successful events to date was a facet of the “Research On Tap” series, a seminar style event that many centers at Boston University co-opt. This particular event, organised by Daniel Shahar, gave students the opportunity to present their thesis in a short time frame to a panel of judges. And, according to Lapointe-Leclerc, this event attracted one of the highest turnouts of any event the society had hosted: “About 70 to 80 people showed up, and we had 12 presenters.” Lapointe-Leclerc highlights the importance of connecting community and research.
“If we ask people to leave their research for two hours, it’s really hard to convince them unless there’s a clear benefit.” Although Lapointe-Leclerc wasn’t the acting president for this specific “Research On Tap” production, he plans to bring it back next year, along with further initiatives, including more socials and professional and scientific development events.
Lapointe-Leclerc believes that building a broader sense of community at the Photonics Center is key to fostering both professional and personal growth. For him, it’s not just about research, but about creating connections beyond labs. “When I meet someone, obviously, I’m interested in their research, but I’m also interested in their hobbies,” he says. The person behind the research is important, and if you can create that space for students to connect on multiple levels, it helps create a more well-rounded and supportive environment.
“I think it’s important. To be the best student you can be, first be the best person you can be.”