In a quiet lab just north of the University of Waterloo’s main campus, Kent Ueno and his team are doing something that sounds like science fiction: trapping individual rubidium-87 atoms in space and manipulating them with lasers. It’s part of a larger effort to build a quantum simulator, a tool that uses one quantum system to mimic other complex quantum systems. Ueno and his team achieve this by confining atoms in optical tweezers and exciting them to Rydberg states.
“It’s kind of like building a playground for quantum physics,” Ueno explains. “You create a system you can control really well and then use it to explore other systems that are harder to access, either because they’re too expensive or too complex to build.”
Ueno’s fascination with quantum physics began in high school, when a physics class unexpectedly clicked in a way nothing else had. That spark led him through undergraduate studies and into a Doctor of Philosophy (PhD) program at the Institute for Quantum Computing (IQC), where the more he learned about quantum mechanics, the more he realized how much remained unknown. “It’s that explorer’s desire,” he says. “The deeper you go, the more mystery you find.”
Lasers that cool, atoms that hover
While most people assume lasers are used to heat, Ueno’s research uses lasers to cool hundreds of atoms to the point where they can be individually suspended in air. This level of control opens doors to studying exotic quantum phenomena and potentially discovering new quantum materials. “If we can use our simulator to learn about materials that lead to the development of practical quantum devices, it would be groundbreaking,” says Ueno.
A community that pushes you forward
Ueno discovered a strong sense of community at the University of Waterloo, inspired by a supervisor who encouraged him to step outside his comfort zone and engage with other researchers. He recalls working alone in the lab while a conference was happening just next door. His advisor walked by, noticed he wasn’t attending, and said, “If you can’t walk a minute to engage with the community, you’ll never be a scientist.”
“That stuck with me,” Ueno says. “The more time passes, the more I realize he was right. Actively engaging with the community offers the greatest opportunity to grow. I learned that you can do a lot on your own, but you also need other perspectives. It’s one of my favorite memories of my degree so far.”
The diversity of Waterloo’s research community has also shaped Ueno’s perspective. Working alongside peers from around the globe has shown him how different educational backgrounds can converge into a shared scientific goal. “It’s enriching to attack the same idea from different angles,” he says.
Asking the Right Questions
For Ueno, learning how to ask the right questions has been a cornerstone of his growth at Waterloo.
“It’s not just about engaging with the field; it’s also about knowing how to frame your work in terms of impact and purpose,” he says. For students unsure how to define this framework, he recommends looking at grant applications as templates for strong research questions. “They force you to think about feasibility, significance, and why society should care.”
As a final piece of advice to future and prospective graduate students, Ueno emphasizes that genuine curiosity is a great motivator, and team alignment, its facilitator. “Ask questions to understand, not just to challenge,” he says. “I have found that we get our best results when all team members are curious about the same key questions.”
Looking ahead
As Ueno nears the end of his PhD, he’s focused on continuing research that keeps his curiosity alive. Whether through a postdoctoral position, private research or a startup, he wants to explore the cutting edge of quantum physics.