Quantum Breakthrough Uncovers Hidden Molecular Secrets

Using quantum sensors, Penn engineers transformed NQR spectroscopy, allowing for atomic-level accuracy to reveal molecular features and promoting molecular diagnostics, drug discovery and protein research.

FREMONT, CA: A quantum breakthrough has been made by the engineers at the University of Pennsylvania School of Engineering and Applied Science who have transformed nuclear quadrupolar resonance (NQR) spectroscopy by using quantum sensors to detect signals from individual atoms. This breakthrough, which was detailed in Nano Letters, opens the door to transform uses in molecular diagnostics, protein research and drug development, thereby setting a new era of scientific innovation.

Conventional spectroscopic techniques obscure minute differences between individual molecules by using signals averaged from trillions of atoms. These restrictions impeded progress in areas such as protein studies, where minute structural variations determine function and differentiate between health and illness. This obstacle is removed by the new scientific method, providing unmatched accuracy for investigating molecule interactions at the atomic level.

According to Lee Bassett, Associate Professor of Electrical and Systems Engineering and Director of Penn's Quantum Engineering Laboratory (QEL), this technique allows to isolate individual nuclei and reveal tiny differences in what were thought to be identical molecules. Molecular details that were previously hidden by concentrating on a single nucleus can be revealed, opening up a whole new scale for studying nature's building blocks.

This new unexpected discovery was made during routine research which was examined by Alex Breitweiser, a recent physics doctorate graduate from Penn's School of Arts& Sciences and current IBM researcher. It involved diamonds' nitrogen-vacancy (NV) which are atomic-scale flaws frequently employed in quantum sensing when Dr. Breitweiser found an unusual pattern in the data.

Although they appeared to be an experimental artifact, the periodic signals continued even after thorough investigation. Thanks to technological advancements, Breitweiser’s team was able to identify impacts that were previously impossible to detect using scientific tools, entering into a new regime of physics.

The technique was improved through cooperation with Delft University of Technology in the Netherlands, which combined knowledge of experimental physics, theoretical modeling and quantum sensing. The team was able to develop a technique that can record individual atomic impulses with remarkably high accuracy.

According to Mathieu Ouellet, a recent ESE PhD graduate, this approach displays the distinct characteristics of each nucleus, whereas traditional NQR provides averages.

The future holds great promise for addressing scientific problems in domains such as molecular biology and medication development. Penn Engineering's invention has transformed millions of perceptions of the natural world and hasten developments in materials science, health and other fields by revealing hidden molecular mechanisms.