Scientists could have a new way to explore the hidden behavior of matter, thanks to research involving Queen Mary University of London that uses a quantum computer to carry out a new form of computational spectroscopy.

Spectroscopy is an important scientific technique used to understand the properties of matter. By analyzing how materials and molecules respond to energy or light, researchers can gain insights into their structure and behavior. Computational approaches can complement these experiments by allowing scientists to investigate and predict properties using theoretical models and simulations.

However, quantum systems can be exceptionally difficult to model using conventional computers. The new research, published in Nature Communications, develops a generalized approach to quantum computational spectroscopy that allows researchers to study a much broader range of quantum systems.

While quantum computing could be the future, it is currently plagued by finicky hardware. To make the technology practical, researchers must demonstrate that it consistently and continuously works and performs at scale. In a new study, published in Physical Review Letters, researchers at Lawrence Livermore National Laboratory (LLNL) and the Ion Storage Group at the National Institute of Standards and Technology in Boulder, Colorado, created a robust process for entangling trapped-ion qubits. The result means better building blocks for ion-based quantum computers.

The approach creates a physical link between two trapped ions. Those ions are held in place with an electric field, although they do vibrate naturally. Because they have the same charge, they also repel each other. If one ion moves, it nudges its neighbor.

That shared motion can be used as a messenger between the qubits. In this experiment, the team used radio-frequency and microwave electromagnetic fields to apply a force to the ions. In different quantum states—say, when the qubit is pointing up versus down—the force pushes the shared-ion motion in a slightly different way.

Researchers at the Harvard John A. Paulson School of Engineering and Applied Sciences (SEAS) have demonstrated a promising new way to protect fragile quantum information using nothing but mechanical vibrations—essentially extremely small sound waves. The breakthrough, which comes from the lab of Marko Lončar, Tiantsai Lin Professor of Electrical Engineering, paves a path toward compact, sound-based quantum networks on chips, as well as hybrid quantum systems that combine many different types of quantum bits, or qubits.

The research is published in Nature Physics. Experiments were led by Eliza Cornell, a recent Ph.D. graduate from the Lončar lab and current postdoctoral researcher at Boston University, and Zhujing Xu, a former postdoctoral scholar in Lončar’s group.

The search for materials that can power future quantum technologies is accelerating, but identifying the most promising candidates remains painfully slow. Evaluating whether a material can efficiently emit quantum light requires computationally intensive simulations, making it difficult to screen the vast number of available materials.

Now, researchers from the University of Osaka have overcome this bottleneck with a prediction method that rapidly evaluates promising quantum materials without sacrificing accuracy. They established a high-speed first-principles framework for evaluating atomic-scale color centers that emit single photons and store quantum information.

The findings are published in the journal npj Computational Materials.