The U.S. National Science Foundation has renewed the University of Illinois Urbana-Champaign-led Quantum Leap Challenge Institute for Hybrid Quantum Architectures and Networks, known as NSF HQAN, with $37.5 million in funding over the next five years. The renewal places the institute among the central national efforts to move quantum computing beyond isolated laboratory demonstrations and toward practical, networked machines. Established in 2020 as one of the NSF’s first Quantum Leap Challenge Institutes, HQAN has become a major research hub for quantum information science in the American Midwest, linking universities, national laboratories and technology companies around one of the field’s most consequential challenges: how to make quantum processors larger, more capable and more reliable without simply making a single device impossibly complex.
Rather than attempting to build one enormous quantum processor, HQAN researchers are developing modular quantum architectures. In this approach, multiple smaller quantum processing units, or QPUs, are connected so that they can operate as a coordinated system. The idea resembles the development of conventional computing, where memory, processors, storage and communication components are integrated instead of being forced into one monolithic device. For quantum computers, modularity could be especially valuable because different platforms excel at different tasks. Superconducting circuits can perform rapid operations, trapped or neutral atoms can offer long-lived quantum states and dense arrays, while optical systems can transport quantum information over distance. Connecting these technologies may provide a more realistic path to achieving quantum advantage than trying to scale a single platform indefinitely.
“The first phase of HQAN has made substantial progress in terms of both research advances and building the quantum workforce of the future,” said Brian DeMarco, an Illinois physics professor and the institute’s director and principal investigator. DeMarco said modular quantum computing was largely unexplored when the center began, but has since appeared on the technology roadmaps of major companies. He also emphasized HQAN’s regional role, highlighting its partnerships with the Chicago Quantum Exchange and its contributions to initiatives such as the Illinois Quantum Microelectronics Park. The institute brings together 45 senior researchers from six institutions, including Illinois, the University of Chicago, the University of Wisconsin–Madison, Northwestern University, Stanford University and MIT Lincoln Laboratory.
During its first five-year phase, NSF HQAN reported a series of advances spanning quantum hardware, networking, algorithms and communications. Researchers created entangled states across a four-node superconducting-circuit network, demonstrating that quantum correlations could be distributed among multiple connected modules. Entanglement is a distinctly quantum resource in which the state of one system is linked to the state of another, even when the systems are physically separated. Although entanglement cannot be used to transmit information faster than light, it is essential to distributed quantum computing, quantum sensing and secure communication. The center also achieved quantum-limited millimeter-wave-to-optical transduction using cold atoms coupled to a superconducting resonator, addressing a difficult interface problem between microwave-based processors and optical communication networks.
Other first-phase achievements focused on making modular machines controllable and useful. The team developed reconfigurable superconducting quantum-computing modules and demonstrated autonomous stabilization of remote entanglement in a network. Stabilization is critical because quantum states are fragile and easily disrupted by environmental noise, imperfect control and interactions with unwanted degrees of freedom. HQAN researchers also implemented the first algorithms on a small neutral-atom array and built atom-array modules containing more than 1,000 sites. In addition, they demonstrated a two-species neutral-atom array with gates between different atomic species and realized quantum secret sharing in a triangular superconducting modular processor. The institute says its researchers have published more than 210 peer-reviewed papers to date.
The second phase will focus on closing the gap between individual demonstrations and a complete modular quantum-computing system. Researchers plan to perform basic computational operations, known as application primitives, across modular platforms. These primitives are the building blocks from which larger applications can be assembled, including simulations, optimization routines and scientific calculations. The program will also lay foundations for software capable of coordinating distributed QPUs, including algorithms, compilers and quantum-error-correction protocols. A compiler for a modular quantum computer must do more than translate instructions into pulses: it must decide where operations should occur, how quantum states should move between modules and how communication delays and hardware differences should be managed.
Quantum error correction will be central to that effort. Quantum information is vulnerable to errors caused by decoherence, control imperfections and thermal fluctuations. Unlike classical bits, quantum bits cannot simply be copied to create backups because of the no-cloning theorem. Instead, quantum-error-correction schemes distribute information across many physical qubits so that errors can be detected and corrected without directly measuring the encoded quantum state. In a modular architecture, the problem becomes even more complicated because errors can arise not only inside individual QPUs but also in the interconnects that link them. HQAN will therefore develop improved interfaces for transmitting quantum information, while studying chip-scale integration, more energy-efficient quantum photonics and compact methods for generating entanglement between distant modules.
The renewed center will include 16 industry partners, among them Google, IBM, IonQ and Quantinuum. Their participation reflects a growing consensus across the quantum sector that useful machines will likely depend on interconnected components rather than unlimited expansion of one hardware platform. “Illinois has made a bold commitment to becoming a global leader in quantum technology,” said Rashid Bashir, dean of the Grainger College of Engineering, where NSF HQAN is hosted. Bashir said the collaboration would advance the architectures required to make quantum computing scalable and useful while strengthening the talent and innovation networks needed to support the emerging industry. Preeti Chalsani, Illinois’ chief quantum officer, described HQAN as a driver of quantum research and workforce development for the state, the Midwest and the nation.
The institute’s ambitions extend beyond laboratories and corporate partnerships. Its education programs have brought quantum science to more than 12,000 participants, including students and teachers across the United States. TeachQuantum gives educators a six-week research experience followed by a year of curriculum-development support, while Wonders of Quantum Physics brings quantum concepts into classrooms through demonstrations, hands-on activities and inquiry-based learning. HQAN also trains graduate students and postdoctoral researchers for careers in academia, national laboratories and industry. The center reports that 27 alumni have moved into high-profile industry positions, 17 have accepted faculty roles and nine have joined national laboratories, illustrating how rapidly demand is growing for specialists who understand both quantum physics and engineering.
The renewed program arrives as governments and companies compete to turn decades of fundamental research into practical quantum technologies. Brian Stone, performing the duties of NSF director, said the agency’s long-term investments in quantum science, sensing and communication had created a foundation for more focused efforts. HQAN’s next phase will attempt to transform that foundation into a coherent pathway for modular quantum computing, combining hardware, networking, software and workforce development. The institute’s researchers will work alongside a related NSF institute, the Quantum Leap Challenge Institute for Physics and Engineering of Practical Quantum Error Correction, led by Yale University. Illinois physics professor Wolfgang Pfaff, who is a member of both initiatives, will contribute expertise in superconducting quantum circuits to efforts aimed at identifying and correcting errors in real quantum systems. If the program succeeds, quantum advantage may emerge not from a single spectacular processor, but from a coordinated network of specialized machines working together.
Subject of Research: Modular quantum computing, quantum networking, quantum interconnects, quantum error correction and workforce development.
Article Title: NSF Renews Illinois-Led Quantum Institute With $37.5 Million to Build Networked Quantum Computers
Web References:
https://www.nsf.gov/news/eight-nsf-research-institutes-propel-us-quantum-science-290m
https://hqan.illinois.edu/
https://physics.illinois.edu/people/directory/profile/bdemarco
https://ece.illinois.edu/about/directory/faculty/rbashir
https://physics.illinois.edu/people/directory/profile/wpfaff
Image Credits: Brian Stauffer, University of Illinois Urbana-Champaign; The Grainger College of Engineering at the University of Illinois Urbana-Champaign.
Keywords: Quantum computing, quantum networking, modular quantum architectures, quantum processors, quantum information science, quantum error correction, superconducting circuits, neutral atoms, quantum photonics, NSF HQAN.
