Scientists may have cracked one of quantum computing's most stubborn problems by using a familiar material in a fresh way.
Researchers from Penn State and Colorado State found that gold nanoclusters can mimic the precise spin properties of trapped atomic ions—the current gold standard for accuracy—yet are far easier to make at scale. The work, described in ACS Central Science and The Journal of Physical Chemistry Letters, opens the door for chemistry labs to compete directly in quantum information science.
"For the first time, we show that gold nanoclusters have the same key spin properties as the current state-of-the-art methods for quantum information systems," said Ken Knappenberger, chemistry department head at Penn State who led the team. What's especially exciting, he noted, is that scientists can actively tune spin polarization in these clusters—a property that's usually fixed in most quantum materials.
Why Scaling Matters
Quantum computing faces a core contradiction. The most accurate platforms use gaseous trapped ions that preserve quantum states beautifully—but they're notoriously hard to scale. Pack qubits into solid materials for practical devices, and environmental noise tends to scramble the information.
These nanoclusters neatly sidestep that trade-off.
The monolayer-protected structures—essentially a gold core wrapped in molecular ligands—can be synthesized in relatively large quantities while keeping the fragile properties needed for computation. The team identified 19 distinct spin-polarized states that mirror what trapped ions achieve, but in a form chemists can mass-produce in the lab.
The Chemistry Advantage
Quantum information science has long been dominated by physicists and materials scientists, with chemists mostly watching from the sidelines.
These materials change that. One cluster configuration showed 7% spin polarization—decent but not eye-popping. Swap the ligands, though, and polarization jumps toward 40%—competitive with the best two-dimensional quantum materials physicists have reported.
"This tells us that the spin properties of the electron are intimately related to the vibrations of the ligands," Knappenberger explained. While many physics-built materials have fixed traits, chemists can now dial these characteristics in by tweaking molecular structures—something they've refined for decades.
The clusters act like "super atoms," keeping atomic-like electronic features despite being molecular assemblies. That dual nature gives chemists a new entry point into quantum engineering: they can use familiar synthetic tools to build systems that would be difficult or impossible to create with traditional approaches.
Looking Forward
The Penn State team plans a systematic survey of ligand structures to map how each tweak affects spin polarization—essentially building a molecular toolkit for quantum applications. Different variations could unlock new capabilities for computers, sensors, and devices we haven't imagined yet.
"This is a new frontier in quantum information science," Knappenberger said, emphasizing how chemical synthesis can now be used to design materials with precisely tuned properties.
For an industry hungry for scalable solutions, the answer might have been sitting in chemistry labs all along. The research—funded by the Air Force Office of Scientific Research and the National Science Foundation—suggests the next leap could come not from exotic physics, but from the molecular precision that chemists bring to the table.
Note
Read the full research announcement from Penn State's Eberly College of Science.
