In the everyday world, governed by classical physics, the concept of equilibrium reigns. If you put a drop of ink into water, it will eventually evenly mix. If you put a glass of ice water on the kitchen table, it will eventually melt and become room temperature.
That concept rooted in energy transport is known as thermalization, and it is easy to comprehend because we see it happen every day. But this is not always how things behave at the smallest scales of the universe.
In the quantum realm—at the atomic and sub-atomic scales—there can be a phenomenon called localization, in which equilibrium spreading does not occur, even with nothing obviously preventing it. Researchers at Duke University have observed this intriguing behavior using a quantum simulator for the first time. Also known as statistical localization, the research could help probe questions about unusual material properties or quantum memory.
The results appear online February 18 in the journal Nature Physics.
“In statistical localization, almost all states are frozen,” said Huanqian Loh , assistant professor of electrical and computer engineering and physics at Duke. “This is different from the usual form of localization, where the properties of a system that remain unchanged over time are pinned to a particular site. Here, we see localization even though the conserved properties are rather spread out. Its implications for robustly storing information in a quantum system are quite exciting.”
To understand the concept of localization that Loh and her colleagues observed, imagine your local barista creating a classic “tulip” pattern in the foam atop your latte. Give the cup a swirl, and the pattern eventually disappears as the foam blends into the coffee.
Now imagine a similar situation in which the art persists as a pristine image despite swirling or tapping the cup of coffee. That is the essential surprise behind statistical localization.
“In this imaginary example, we would have expected the elements to mix together—to reach equilibrium—and yet we still somehow see localization,” said Loh. “That is very, very weird, but it could be a powerful feature of quantum mechanics to incorporate into quantum technologies.”
Such statistical localization was theorized to exist in 2020 for certain quantum systems. In these systems, subsets of quantum states are connected to each other and otherwise remain disjointed from all other quantum states. The experimental realization of such fragmented systems, however, demands a high degree of quantum engineering. In this case, Loh and her team turned to a neutral-atom quantum computing platform based on atoms of rubidium.
Using focused lasers, the researchers tightly controlled the position of each atom in a one-dimensional chain. They then excited the atoms’ electrons with another laser so that the atoms’ behaviors became intertwined. Based on the precise atom positions, interactions and engineered quantum evolution when released from their initial state, the researchers were able to choreograph a first demonstration of the localization phenomenon.
The results showed that most configurations of quantum bits remain effectively frozen. Interestingly, the researchers achieved such freezing in a quantum simulator of lattice gauge theory—a basic framework for understanding vast systems ranging from nuclei in astrophysical and collider environments to novel quantum materials.
“Lattice gauge theories provide the language that we use to describe three of the four fundamental forces in nature,” said Natalie Klco, assistant professor of physics at Duke. “Unfortunately, speaking this language to calculate the elaborate predictions embedded in these theories is exceedingly costly, if possible at all, on classical computers. With fragmented state spaces a key feature of gauge theories, these experiments are an encouraging step toward a highly anticipated application of quantum computing for subatomic physics.”
As quantum technologies evolve from small simulators that use only a handful of qubits to larger quantum computers that harness thousands, the ability to retain or store quantum information will become extremely important. Harnessing localized properties of a quantum system that are robust to unpredictable surroundings could be a pathway toward achieving that capability.
This research was supported by the Alfred P. Sloan Foundation through the Sloan Research Fellowship, the NSF STAQ Program, and the National Research Foundation of Singapore.
CITATION: “Statistical localization of U(1) lattice gauge theory in a Rydberg simulator.” Prithvi Raj Datla, Luheng Zhao, Wen Wei Ho, Natalie Klco and Huanqian Loh. Nature Physics, 2026. DOI: 10.1038/s41567-026-03183-w
Nature Physics
Experimental study
Not applicable
Statistical localization of U(1) lattice gauge theory in a Rydberg simulator
18-Feb-2026