Engineering the Quantum Internet

More than just introducing students to the immense complexity and strangeness of quantum mechanics, however, Zhong is also setting the frame for the course.

“We’re not trying to teach them what quantum entanglement is,” Zhong explains. “We’re trying to introduce them to this field and give them a sense for the challenges and the opportunities that lie ahead for quantum.”

That framing is aligned with the research Zhong does as an assistant professor at UChicago’s Pritzker School of Molecular Engineering, where entanglement is seen as a resource to be engineered rather than a mystery to be solved. Zhong runs a lab building nanoscale photonic and molecular technologies aimed at what he calls the quantum internet. His pioneering work in rare-earth quantum nanophotonics earned him the NSF CAREER award  in 2020 and the Sturge Prize in 2025. His research goal, as he puts it, is “to develop critical technologies to make the dream of a quantum internet a reality.”

Zhong’s work, at one level, is driven by simple demand. Quantum computers are becoming real and they will need a way to talk to each other and exchange information. The classical internet can’t do this because a quantum state can’t be converted into ordinary bits and sent like an email or file. That would require what’s called “measurement”—an area of bottomless discussion within quantum science—and that’s what cancels the quantumness of the quantum information. A quantum internet, by contrast, would allow quantum computers to leave their labs and connect. It could also help solve a central engineering problem in the field around how to scale quantum computing without having to build one massive machine.

All of this is closer than most people probably realize. The consensus among his colleagues, Zhong says, is that quantum computers and a quantum internet will likely arrive within the current PhD generation. “So we’re talking five to seven years,” he says.

Quantum Entanglement Allows for Trust

In Quantum Science, Networking, and Communications, Zhong primarily teaches the fundamentals of entanglement and its applications to quantum communication. This part arrives early in the eight-week curriculum with the aim of giving students a high-level understanding of what quantum can offer that classical communication technologies can’t. The course overall is geared toward people who hold a degree in physics or engineering, have since moved into industry, and are now looking to reinvestigate the field. Zhong describes it as a kind of bootcamp for quantum literacy. He also codeveloped the course’s later hardware module, which relates directly to his own daily research building photonic devices and quantum memories.

Zhong’s first move in his discussion of entanglement involves an example from Star Trek. He asks students to think about how the show uses the concept as the basis for teleporting human bodies. Entanglement correlates two particles at potentially galactic distances and describes how in the act of measuring one the other’s state gets instantly fixed as well. Einstein called it “spooky action at a distance” and the spookiness stems from there being nothing physical that explains the correlation, which—bringing it back to Star Trek—is the nonlocal link required for teleporting bodies across a galaxy.

But Zhong quickly returns to earth and notes that “the entanglement we’re talking about in this class is not the Star Trek teleportation type. It’s more about transferring information using quantum entanglement as a resource.”

This leads into a striking and counterintuitive scenario that overturns a core assumption every internet user has today, which is that you have to trust the company carrying your data not to read or change it, or hand it to anyone else. He asks students to imagine a near future where companies like Verizon or AT&T offer quantum network services. The challenge he then gives students is to begin designing a communication protocol that’s self-proven, which means it’s fully secure and doesn’t require trust in the service provider.

Technically called device-independent quantum communication, it means the security of the information exchange is rooted in physics rather than human trust. While in conventional encryption you still have to trust the device manufacturer, the network carrier, and the protocol designer, the quantum version needs none of those because the security comes from the physics of entanglement itself.

“There’s nothing like this in the classical world we’re familiar with,” Zhong says. “I designed the course to let them start thinking about the concept at a deeper level. The goal is for them to be active participants and design something.”

To pursue the problem, he breaks the class into small groups and then hops between rooms to hear their responses and push their thinking further where possible. He often comes away having learned something himself. “They ask very good questions that often force me to rethink at a fundamental level what quantum entanglement is all about and the best way to present it to students.”

A View of the Frontier

Later in the course, students work with SeQUeNCe, an open-source quantum network simulator developed by Zhong’s lab in collaboration with Argonne National Laboratory. Alex Kolar, the graduate student in Zhong’s lab who led the simulator’s development, teaches the module himself. Students populate a network with nodes representing cities and set the fiber distances between them. They then equip each node with hardware—like photon sources, detectors, and quantum memory—and by running the simulation, they see what secure bit rates the network produces. The tool gives students hands-on intuition for network designs that would otherwise take years to realize in physical hardware, which is how Zhong’s own lab uses it as well.

Learning and Networking in a Quantum Hub

At a broader level, it’s the sense of an intensely active research frontier taking place in Chicago today that students come to feel directly. Zhong even compares the city’s emergence as a quantum hub to Silicon Valley in the ’70s or ’80s. “There’s that sense of excitement and also a deeply interconnected ecosystem that means I can find a collaborator to discuss scientific topics without leaving Chicago,” he says.

That ecosystem is also shaping student trajectories after they finish the course. Through the Chicago Quantum Exchange, the program connects students to corporate partners exploring quantum networking, from telecom carriers to financial firms, which opens up future employment prospects. Zhong notes that these employers often prefer candidates who already have a technical background and need only some retraining in quantum, rather than fresh graduates. One former student, an engineer at a navy research facility, took the class to connect with the quantum side of his work and now helps organize quantum research conferences.

In fact, the Midwest now hosts what is arguably the highest concentration of national quantum research centers in the country, with the Chicago Quantum Network already connecting UChicago to Argonne and Fermi National Labs and running demonstrations of physically secure cryptographic keys today.

Quantum Satellite Software

Looking ahead, Zhong’s lab is starting to build quantum satellite hardware. The point of satellites, he notes, is to overcome the physical limitations of fiber. “Just by tilting the beam angles a little bit, you are now at a different continent.” He hopes to bring that work into the course as the program matures, possibly even letting students control a quantum satellite remotely. The frontier keeps moving and Zhong makes sure his students keep pace.