Industrial researchers, including collaboration principal investigator Linda Mauron, have been pushing the limits of quantum physics. They reported the results in Nature Physics just last month. Titled “Predicting topological entanglement entropy in a Rydberg analogue simulator,” the paper explores the intricate properties of topological quantum systems. The research, appearing August 17, 2025, in Communications Physics, proposes a new way forward using Rydberg atom lattices. It uses a state-of-the-art time-dependent variational Monte Carlo (t-VMC) scheme for the analysis.
The paper’s DOI is 10.1038/s41567-025-02944-3 This post has been carefully edited by Lisa Lock and fact checked by Robert Egan. This research furthers the work of others, especially a landmark study by Semeghini et al. that paved the way to probing topological spin liquids.
The Experimental Framework
Inspired by this direction, the researchers performed laser-focused experiments with a Kagome lattice arrangement. They showed that topological quantum systems can possess exotic features, contingent on the connectivity structure of their underlying lattice. We fix the blockade radius, Rb, to be 2.4a. This particular choice allows for strong and/or non-negligible coupling between all atoms in the lattice.
The t-VMC scheme proved instrumental in the development of the research. This method does not involve any approximations about the shape, size or time evolution of the system. This malleability gives researchers more freedom to focus on what’s most important about the quantum state. They are able to do it without losing accuracy in their simulcasts.
Linda Mauron elaborated on this innovative method by stating, > “To keep it simple, instead of learning the probabilities of every single state that could possibly exist (which, for a system of N spins, equals 2N states to learn), we encode the quantum state with a few parameters which instead learn the features of the state.”
Key Findings and Future Directions
Mauron’s paper uncovers an interesting (and gratifying) surprise. Their mathematically rigorous, general approach can quickly simulate any experimental protocol that can be realized with Rydberg atom simulators, and importantly, without any building approximations. This breakthrough finally allows us to bring the simulation up to larger, more meaningful system sizes. It’s a big step up in quantum simulation capacity and capability.
“We demonstrated the capacity of our approach to faithfully simulate an experimental protocol on a Rydberg atom simulator, without making any approximation, while still being able to scale up this scheme to meaningful system sizes.”
The research team’s next goal is to apply and generalize their techniques to simulate more complex quantum devices and quantum protocols. Mauron expressed her enthusiasm for future research directions, stating, “We are now focusing on the ability to simulate additional quantum devices and protocols using similar techniques.”
The investigations continue to help understand the traits of these “protocol” ready states. Mauron emphasized the importance of understanding these features, remarking, “We are further investigating the characteristics of the state prepared through the herein-described protocol.”
Challenges and Considerations
Even with these successful results Mauron and her team accepted there were some issues faced during their simulations. What was worse was that most existing numerical benchmarks used to validate these kinds of setups would miss very important aspects of experimental implementations with Rydberg atom platforms. This mismatch would result in unfavourable and misleading comparison with other experiments.
She stated, “We realized that all the numerical benchmarks, as for many other experiments occurring in Rydberg atom platforms, failed to capture some of the central particularities of the experimental setup and were thus potentially wrongly compared.”
Their work highlights a fundamental aspect of topological quantum systems: properties are largely dependent on the overall connectivity of their lattice rather than local interactions or microscopic structures. We hope that this breakthrough will inspire deeper investigation and understanding of rich and complicated quantum behavior.