Crystal Noel: Hot on the Heels of a Long-Lasting Qubit

Crystal Noel will join Duke University’s Department of Electrical and Computer Engineering and Department of Physics and add her experience in quantum error correction to the rapidly expanding Duke Quantum Center (DQC). Noel will begin as a research scientist in the summer of 2021 and join the faculty in summer 2022.

Noel has spent the past year as a postdoctoral associate in the lab of University of Maryland professor Chris Monroe, part of a team building an IARPA-funded quantum computer system called EURIQA—the Error-corrected Universal Reconfigurable Ion-trap Quantum Archetype.

Though until recently the members of the DQC team, which include Duke Engineering’s Jungsang Kim and Kenneth Brown, have been spread across the eastern seaboard, they shared a single approach to quantum computing—ion trapping, which uses lasers to cool and manipulate ions held in a chamber where background gases are lower than in the vacuum of space. In this rarefied environment, the trapped ions can hold a superposition—a phenomenon of physics that allows them to exist in two states simultaneously. These kinds of ions serve as the quantum bits, or qubits, at the heart of EURIQA.

But the tiniest environmental disturbance can cause qubits to toggle on or off in the middle of calculations.  

“If a qubit flips to a zero or a one in the middle of a calculation, that’s an error,” said Noel. “You have to come up with a protocol by which you can probe the system, find errors, and fix them. What if I make three copies of the qubit, and only one flips? Then I know what the error was. But we can’t just copy a qubit like we would a normal bit. It requires more cleverness in construction.”

If one perfects a method that continually corrects the environmental factors disrupting a system, said Noel, one could create a qubit with enough stamina to complete computing tasks that are exponentially out of reach for current computer technologies.

As of now, EURIQA has evolved to the point where the frequent calibrations needed to keep the system operational are run remotely, leaving Noel more time to further refine software and work with theorists to imagine the next generation of quantum computers, whose computational capabilities will increase exponentially as qubits are added. “We need to think farther ahead,” said Noel. “As of now there’s no clear picture of how we’re going to go from 20 qubits to 100. How can we do that with smart engineering of the traps themselves? At this point in the field, it’s more and more important to use good engineering practices and design for the future.” 

The EURIQA system located at the University of Maryland will also relocate to Duke, serving as the temporary flagship computer of DQC; the center will feature a user-facing lab where theorists will be able to explore problems far too complex for a classical computer to handle. 

“DQC will be very different from what is currently offered commercially in the Cloud, because we’ll be able to interact with the theorists and customize the machine as needed.”

Crystal Noel

Noel said the opportunity to be part of the Duke team launching this unique quantum computing hub was the main motivator for her move. “DQC will be very different from what is currently offered commercially in the Cloud, because we’ll be able to interact with the theorists and customize the machine as needed,” said Noel. “We’re going to be bringing in collaborators right away. It’s going to be a fast-paced, exciting time, and the collaboration among experts in a single building is really going to accelerate the research.”