In Assistant Professor Yannick Salamin’s lab, the shelves are fuller every day. Delivery boxes arrive like clockwork. Students move equipment back and forth. Salamin says, pardon the dust.
“Sorry about the mess,” he says, pushing some wires to the side. It’s all part of the process to launch a new lab.
Salamin got the keys to the space when he started at CREOL, the College of Optics and Photonics in August 2024. Now his setup process is about to accelerate, thanks to a new infusion of funding from the Ralph E. Powe Junior Faculty Enhancement Award.
“I feel amazing and truly honored by this award,” Salamin says. “I’m excited that it’s also shining a light on the important work we’re doing.”
Salamin is one of 36 faculty members nationwide to be honored with the award, which is sponsored by the Oak Ridge Association of Universities (ORAU). The initiative aims to support select junior faculty members with seed funding to help launch their research projects.
In Salamin’s case, that’s the world of quantum nonlinear photonics (QNP), a group he hopes to grow as fast as his lab. The $5,000 from ORAU, matched with another $5,000 from the university, will allow him to recruit more students as he continues to install equipment. The QNP group’s broad goal is to develop experimental systems to study and shape the quantum properties of light.
Quantum light is typically generated within special structures known as optical cavities. Understanding what goes on inside of them is key to improving how we develop and control quantum states of light — and ultimately to advancing quantum technologies.
While optical cavity systems have been around for some time, Salamin says that studying what happens inside them has been challenging. He compares it to a black box.
“You see the output, but you don’t know what’s happening within,” he says. “Yet, that inner process is where the real magic happens.”
Now, thanks to recent advances, Salamin and his team can not only peer inside these quantum systems, but they also hope to take things a step further—by coupling other objects, such as atoms and quantum emitters, to their platform. This would allow them to manipulate and control the behavior of these coupled systems using precisely engineered quantum light.
“That’s very exciting,” Salamin says, “Because you can then use the atom as a quantum sensor.”
Real-time sensing at the atomic level has broad applications that include:
- Detecting extremely weak magnetic fields in the brain, helping researchers study neurological disorders like Parkinson’s disease and Alzheimer’s disease.
- Precision acceleration detection, which is critical for enabling GPS-free navigation, vital for autonomous systems or environments where satellite signals are unavailable.
- Future advances in quantum computing and efficient probabilistic machine learning systems.
Opening the “Black Box”
Optical cavity systems are spaces composed of mirrors that trap the light inside.
“You’ve probably had this experience in a bathroom,” Salamin says. “You have one mirror in front of you, and one behind you, and you see yourself many times, because the light is bouncing back and forth. But at some point, the closer you get to normal incidence, when you’re perpendicular to the mirror, you just see one of you, because you’re blocking the beam. This is exactly the problem: We want light to bounce many, many times, but if we put a detector in there to see what’s inside, we block the beam.”
How do they see the beam? Salamin says the famous Schrödinger’s cat thought experiment is a good analogy. In this thought experiment, a hypothetical cat is placed in a box where it may or may not be poisoned. The cat could be considered alive or dead until it is observed.
Salamin says a way to determine whether the hypothetical cat is alive would be to shake the box and listen for a sound. His group is applying a similar concept of determination to measure the quantum properties of light inside the cavity.
“If you think of a light beam, traditionally you think of a little wave” he says. “That has a nice, sinusoidal shape, but the reality is, down at the quantum level of light, the waveform is actually quite blurry, like a noisy signal.”
The concept is rooted in the fundamental uncertainty associated with high-precision measurements at the quantum level, Salamin says. That means the ability to accurately determine the phase or amplitude of the light is limited. The solution is to produce a quantum state of light by “squeezing” the noise, or blurriness.
“Squeezing the lemon juice,” Salamin says. “You can represent this uncertainly in a circle, where you have the same amount of uncertainty everywhere. If one axis represents the phase, and the other represents the amplitude, squeezing can reduce the blurriness for one property.”
For example, the amplitude can become clearer, at the cost of further obfuscating the phase — but Salamin says that’s just fine for certain applications, like spectroscopy.
“Say you want to measure if there was signal absorption or not,” he says. “With this high precision, you can determine what type of molecules are in gas or in the materials you’re trying to measure.”
Salamin says squeezing in the other direction would obscure the amplitude but focus the phase — a useful technique for the famous Laser Interferometer Gravitational-Wave Observatory experiment to detect gravitational waves.
Another big goal is to experiment with bosonic quantum states, which can be used to create more robust quantum bits for computing. That robustness is essential to reduce the bits’ sensitivity to external influences that could compromise their quantum state.
Salamin’s QNP group is laser-focused on building onto the field’s knowledge base.
Finding a Family
Salamin’s path to UCF began as he wrapped up his postdoctoral years at the Massachusetts Institute of Technology (MIT). His search for a faculty position led him to CREOL in more ways than one.
“If you look at other big schools, they usually have large departments like Physics or Engineering,” Salamin says. “Within those, you might find some optics groups — but it’s usually just a small number, maybe two or three of them. At CREOL, it’s the opposite—everyone here is dedicated to optics, with expertise spanning from fundamental science to applied research. It creates a uniquely focused and collaborative environment.”
Salamin cites the tight-knit atmosphere at CREOL as a significant asset for the optics and photonics community — saying collaboration is easy among his neighbors.
“What amazed me when I came here is that there’s really this big sense of family,” he says.
About the Researcher
Yannick Salamin joined CREOL, the College of Optics and Photonics in 2024 as an assistant professor. Before this, he was a postdoctoral fellow at the Massachusetts Institute of Technology, working with Professor Marin Soljačić’s group. His research focuses on the exploration of the quantum properties of light and the complex dynamics of nonlinear optical systems.
Salamin received his bachelor’s degree in electrical engineering from the University of Applied Sciences of Western Switzerland in 2010 and his master’s degree in electrical engineering from Zhejiang University, Hangzhou, China, in 2014. He earned his doctorate from ETH Zurich, Switzerland, in 2019, where he conducted research under the supervision of Professor Juerg Leuthold, developing integrated plasmonic platforms for efficient nonlinear and optoelectronic devices.
