Picture electrons not moving in straight lines, but spiraling their way through a molecule.
This is precisely what a team of international scientists from IBM, The University of Manchester, Oxford University, ETH Zurich, EPFL, and the University of Regensburg has achieved: observing a half-Möbius electronic topology within a single molecule, a type of quantum matter that was previously unknown.
Published in Science, this breakthrough represents a significant advancement in both chemistry and quantum computing. The molecule they created is unprecedented, and its behavior was understood using quantum computing to model the quantum principles that electrons adhere to.
Alessandro Curioni, IBM Fellow, Vice President, Europe and Africa, and Director of IBM Research Zurich, stated, “First, we designed a molecule we believed could be synthesized, then we constructed it, and finally, we confirmed its unique properties with a quantum computer.”
Quantum entanglement and topology are closely intertwined
Decades ago, Richard Feynman envisioned a computer capable of simulating quantum physics, and this study has brought us closer to that dream. The molecule, C₁₃Cl₂, was meticulously built atom by atom at IBM, showcasing a new way to explore matter at its most fundamental level.
When examined using advanced microscopes, the molecule displayed an intriguing electronic twist: electrons rotate 90 degrees with each loop, requiring four complete loops to return to their starting point.
This unique electronic topology can be manipulated to switch between different states, demonstrating that scientists can intentionally engineer electronic structures.
Understanding this molecule necessitated the use of quantum computing due to the complex entanglement of electrons, which is challenging to simulate on classical computers. Quantum computers, however, operate under the same principles as electrons, making them ideal for studying such phenomena.
A novel quantum state of matter could drive future technologies
Using IBM’s quantum hardware, the team uncovered the mechanism behind the molecule’s behavior, revealing a helical pseudo Jahn-Teller effect.
Dr. Igor Rončević of Manchester University described it as, “Topology can act as a switchable degree of freedom, offering a powerful method to control material properties.”
Dr. Jascha Repp of Regensburg added, “It’s incredible that a tiny molecule can possess such a complex electronic structure, so twisted and unusual that it challenges our understanding.”
Dr. Harry Anderson, co-author and Professor of Chemistry at Oxford University, remarked, “The Lewis structure of C₁₃Cl₂ already indicates its chirality, as confirmed by experiments and quantum calculations. The ability to interconvert enantiomers using voltage pulses is truly remarkable.”
Journal Reference:
- Igor Roncevic, Fabian Paschke, Yueze Gao et al. A molecule with half-Möbius topology. Science. DOI: 10.1126/science.aea3321
