A novel phase of matter has been achieved by a team of American researchers, finally realizing a theoretical quantum prediction using nanoscale building blocks, a breakthrough that could pave the way for room-temperature quantum computing.
Researchers at Brown University and the University of Michigan College of Engineering revealed how they briefly stabilized the novel state of matter in a nanoparticle superlattice in a recent paper published in the journal Science. They say their work provides a new method for engineering classes of materials with custom-shaped nanoparticles, which could be applied to quantum computers and other quantum applications.
Quantum Blocks
“Our work is a little bit like kids playing with LEGO blocks,” said co-author Ou Chen, an associate professor of chemistry at Brown. “We synthesize unique nanoscale building blocks and stack them into interesting structures. In this case, we were able to stabilize these theorized transitional structures and demonstrate important quantum optical properties.”
Most metals form in one of two primary groups of crystal structures. The first is face-centered cubic (FCC), the tightest packing arrangement for spherical particles, typically forming a cube with a single particle at each corner and at the center of each face. The other type is body-centered cubic (BCC), a more loosely packed structure in which single particles are still present at the corners, but instead of each face being centered on a particle, one sits at the center of the entire arrangement.
For the most part, atoms form one of these structures as they arrange into a metal, yet at high temperatures, some metals can switch from one structure to another. When it reaches 912° Celsius, Iron will transition from BCC to FCC. One explanation proposed for the transition is the Nishiyama-Wassermann pathway, which suggests that, due to the lower symmetry of the transition phases between FCC and BCC, these phases are fleeting.
Testing the In-Between States
The American team behind the recent research decided to test this idea, fabricating one of those low symmetries in between phases with silver nanoparticles
“Materials scientists have cared about how to control the amount of FCC and BCC in their metals for a long time, but the transitions between these phases have been hard to study because they are so unstable,” said co-author Tim Moore, an assistant research scientist at the University of Michigan. “Being able to observe these structures is a fundamental breakthrough in materials science, and it gives us greater control over nanomaterial engineering.”
At the heart of the team’s work was the truncated octahedron, or “mecon,” a 14-sided polyhedron formed by cutting off the vertices of a diamond, producing an intermediate shape between a cube and sphere.
As the team synthesized silver nanoparticles, they varied the heat level during production, resulting in a spectrum of shapes ranging from cubic to spherical, which were coated with long, sticky molecules that bound the particles. They found that the sticky molecules were required for the particles to assemble themselves into the intermediate shapes predicted by the Nishiyama-Wassermann pathway.
Near Quantum Behavior
Once the particles self-assembled into variously shaped nanoparticle superlattices, the team tested their behavior with computer simulations and physical observations.
The superlattices show evidence of a process known as deep-strong light-matter coupling, in which silver electrons vibrate in unison with light waves, becoming so hybridized they could no longer be treated independently. The similarity of this state to quantum entanglement leaves the team hopeful that their superlattice can be applied to quantum work in the future.
Crucially, this action occurs at room temperature, whereas in previous instances it occurred only at very cold temperatures. This means the work could be useful for developing quantum technologies, which have been limited by the extreme cold required.
“One of the major challenges in quantum computing is maintaining coherent quantum states without requiring extremely low temperatures,” Chen told The Debrief in an email. “Our work suggests that carefully engineered nanoparticle superlattices may provide a scalable materials platform where strong and coherent light–matter interactions can persist at room temperature.”
Quantum Applications
“In the long term, such systems could potentially be used to create or manipulate quantum states for applications in quantum information science, including quantum communication, sensing, or photonic quantum technologies,” Chen said. “However, it is important to emphasize that this research is still at the fundamental physics and materials discovery stage. We are not yet building a room-temperature quantum computer, but rather exploring new material platforms that may help enable future quantum technologies.”
As research continues, the team is focused on more precisely controlling the superlattices’ quantum optical properties.
“Specifically, we are interested in: Engineering nanoparticle architectures that produce even stronger and more controllable light–matter coupling; Exploring how structural order, particle shape, and lattice symmetry influence quantum optical behavior,” Chen explained, “and Integrating these materials with photonic and optoelectronic platforms for potential quantum-device applications.
“More broadly,” Chen concluded, “we see this work as opening a new direction where nanoscale self-assembly can be used to engineer emergent quantum optical properties that do not exist in the individual nanoparticles alone.”
The paper, “Stabilizing In-Transition Phases of Superlattices Through Shape Control of Silver Nanocrystals,” appeared in Science on May 28, 2026.
Ryan Whalen covers science and technology for The Debrief. He holds an MA in History and a Master of Library and Information Science with a certificate in Data Science. He can be contacted at ryan@thedebrief.org, and follow him on Twitter @mdntwvlf.
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