Scientists at the University of California, Riverside (UCR) have made significant strides in the quest to build larger and more reliable quantum computers. In a recent study published in the journal Physical Review A, researchers demonstrated that multiple small quantum chips can be interconnected to function as a single, powerful quantum system, paving the way for scalable quantum architectures that could revolutionize how we approach data processing.
Quantum computers have already found applications in fields such as chemistry, materials science, and data security, but many current systems remain too small for extensive practical use. The UCR team’s research highlights the potential of linking existing quantum chips to enhance their capabilities without the need for entirely new hardware.
Mohamed A. Shalby, the first author of the study and a doctoral candidate in the UCR Department of Physics and Astronomy, emphasized that their work is not about innovating new chip designs. Instead, they explored how current technology could be adapted to create larger and more effective quantum systems. “This is a foundational shift in how we build quantum systems,” Shalby noted.
A key challenge in creating larger quantum systems is scalability—the ability to process increasing amounts of data without a decline in performance. Similarly, fault tolerance, the system’s capacity to detect and correct errors autonomously, is critical for ensuring reliable outputs even in the presence of hardware imperfections.
Shalby explained that past attempts to connect multiple small chips faced significant obstacles due to the “noise” generated from connections between chips, particularly when housed in different cryogenic refrigerators. This noise often disrupted the system’s ability to correct errors.
However, the UCR-led team found a promising solution: their simulations revealed that even with links between chips being up to ten times noisier than the chips themselves, the overall quantum system could still successfully detect and correct errors.
“This means we don’t have to wait for perfect hardware to scale quantum computers,” Shalby said. “As long as each chip operates with high fidelity, links can be ‘good enough’ rather than perfect, allowing us to construct a fault-tolerant system.”
This breakthrough could pave the way for the development of more robust and scalable quantum computing technologies, ushering in new possibilities for research and applications across various scientific fields.
