NSF Award Supports UAlbany Researcher’s Mission to Make Quantum Accessible - University at Albany

Walid Redjem talks quantum photonics and why he's as invested in helping people understand quantum science as he is in advancing it. (Photo by Patrick Dodson) By Bethany BumpALBANY, N.Y. (Sept. 24, 2026) — Walid Redjem has been fascinated by the strange world of quantum science since he was a young boy, when a classroom teacher showed a video about the double-slit experiment.The famously counterintuitive science describes how matter and energy behave at the smallest scales, where particles can exhibit behavior with no classical equivalent, such as existing in a superposition of different states or producing different outcomes depending on how they are measured.Now, with the support of a five-year, $588,285 CAREER Award from the National Science Foundation, the assistant professor in the Department of Nanoscale Science & Engineering at UAlbany's College of Nanotechnology, Science, and Engineering is advancing his research in quantum photonics while working to make the field more accessible to students and the public.

Walid Redjem Redjem joined UAlbany in 2024 as an Empire Innovation Assistant Professor after completing a postdoctoral appointment in electrical engineering and computer science at the University of California, Berkeley. He holds multiple degrees in physics, mathematics and quantum devices from universities in France and Canada. He now leads the Quantum Photonics Lab, which develops photonic technologies for quantum computing, communication and sensing.The CAREER Award supports Redjem’s goal of building a silicon photonic chip that combines two different ways of encoding quantum information, known as discrete-variable and continuous-variable approaches, on a single platform. This hybrid approach could make it easier to link many quantum bits, or qubits, together — a critical step toward large-scale quantum computing. The project also includes the development of a portable, chip-based toolkit designed to bring hands-on quantum experiments into K-12 classrooms and undergraduate labs nationwide.We caught up with Redjem to talk about the science behind his project and why he is as invested in helping people understand quantum science as he is in advancing it.What drew you to the field of quantum photonics?When I was about 10, a teacher showed our class an animated video called Dr. Quantum explaining the double-slit experiment.Imagine a barrier with two narrow slits and a screen behind it. You send photons toward the slits one at a time, and each is seen on the screen as a single particle at a specific position. But repeat the experiment many times and the photons gradually form an interference pattern — something we normally associate with waves. Quantum mechanics tells us that, before we measure it, the photon exists in a superposition of both possible paths and interferes with itself. Yet if we place a detector at the slits to determine which path the photon took, the interference disappears.As a child, I found that completely puzzling. Honestly, I still do. We can calculate the outcome of this experiment with extraordinary precision, but what quantum mechanics tells us about physical reality remains difficult to interpret.Physicists realized these effects could be used to encode and process information. With millions of “slits,” photons could explore an exponentially large number of paths simultaneously — with a quantum processor able to solve certain problems like navigating a maze, factoring large numbers or simulating complex molecules exponentially faster than a classical computer.The theory is one thing, but the question that fascinated me as a child is still what motivates me today: How can we turn the theory into reality?What is quantum photonics and how does it show up in everyday technology?Photonics is the science of generating, guiding, manipulating and detecting light, and it plays a central role in everyday technology. The Internet relies on optical fibers to carry information as pulses of light. Smartphones contain cameras, lasers and optical sensors. Medical imaging, manufacturing, autonomous vehicles and data centers all depend on photonic systems.Quantum photonics uses many of the same components, but in a regime where light’s quantum properties become important. Instead of working only with bright laser beams, we can generate and manipulate individual photons, entangled pairs and other quantum states. Modern optics and telecommunications technology already provides a foundation for controlling light at the quantum level, with potential applications in computing, secure communication and sensing.Silicon photonics lets us shrink optical experiments that once filled a laboratory table onto a tiny chip fabricated much like modern microprocessors — essentially bringing the idea of those “millions of slits” onto a chip.What problem does your CAREER project attempt to solve?The long-term goal is to build a quantum processor that uses light to solve certain problems much more efficiently than a classical computer. This requires the creation of quantum correlations (called entanglement) among thousands or even millions of qubits. But single qubits are extremely fragile, which makes building large quantum processors a real challenge.My CAREER project addresses this with a hybrid architecture that combines light’s particle-like (discrete-variable) and wave-like (continuous-variable) properties. Rather than entangling qubits directly, we couple each one to a laser beam that then acts as a quantum bus mediating correlations between multiple qubits.What is the advantage of this hybrid approach in quantum photonics?Single photonic qubits are fragile — if one is absorbed, scattered or missed by a detector, its information can be lost. Lasers, by contrast, contain many photons and can be generated, transmitted, manipulated and measured with very high efficiency using mature photonic technology.My CAREER project will attempt to answer whether a very bright laser beam can mediate entanglement between fragile qubits. In our approach, the optical field acts as a quantum bus, carrying information about each qubit through the photonic circuit. By interfering and measuring fields associated with different quantum emitters, we can generate entanglement between qubits that never directly interact — making entanglement generation more efficient, scalable and tolerant of imperfections.A major goal of this project is to make quantum education accessible. How do you plan to do that?Quantum mechanics can be difficult to comprehend — even for physicists — but it’s the reality we live in.My goal is to bring quantum mechanics into any classroom through an affordable, portable education toolkit. The experiments will be integrated onto a silicon chip that fits in the palm of your hand and can be used to demonstrate quantum phenomena in K-12 classrooms, undergraduate labs and public outreach events, including demonstrations inspired by the double-slit experiment.I hope this toolkit reaches schools nationwide. My goal is not only to teach quantum mechanics, but to demystify it — showing students it’s something they can observe, explore and experiment with themselves.