Physicists Discover a Fundamental Limit to Electrical Resistance
Summarize this article with:
Share Facebook Twitter LinkedIn Pinterest Telegram Email Reddit An artist’s impression of the resistivity that results from cold atomic collisions. Researchers investigating interaction-induced resistivity of ultracold atoms in a checkerboard-like landscape observe a quantum enhancement of their likelihood of colliding, akin to how ducks that move in bubbles would collide as if they were the size of the bubbles, rather than their actual size. Credit: Haiwei HouA quantum simulation found a ceiling on resistivity caused by electron collisions.Every time electricity flows through a wire, some of its energy is inevitably lost as heat because electrons collide with one another and with the material around them. But just how much can these collisions increase electrical resistance? A new study suggests there is a fundamental limit.To investigate, researchers from the University of Toronto, L’École Normale Supérieure in Paris, and Lehigh University turned to an unusual stand-in for electrons: ultracold potassium atoms cooled to temperatures just above absolute zero.By precisely controlling how often the atoms collided, they found that resistance increased only up to a certain point before leveling off. The discovery provides rare experimental evidence for a microscopic limit to resistivity and could improve scientists’ understanding of electron behavior in quantum materials.“Electron-on-electron collisions are known to increase resistivity in some pure materials,” explains Professor Joseph Thywissen in the Department of Physics and the Center for Quantum Information and Quantum Control in the Faculty of Arts & Science at the University of Toronto, senior author of a study published in Physical Review Letters. “The energy produced by electrical resistance shows up as heat. Transmission lines, for instance, lose up to 8% of the generated electrical power. Resistivity is also interesting to study because it can be a signature of new physics in materials.”Light lattice isolates collisionsThe experiment relied on an optical lattice, a grid made of light that holds atoms in place and allows them to act like electrons moving through a solid. This controlled setup let the scientists recreate extreme conditions that ordinary solid materials cannot reach and focus specifically on how collisions affect resistance.Physics doctoral students Robyn Learn and Frank Corapi, co-first authors, with Professor Joseph Thywissen. Credit: Jo-Anne McArthur“We observed that the atoms, which are only a few nanometers in size, bump into each other as if they were much larger,” says Thywissen. “This quantum enhancement of the effective atom size makes collisions on a given lattice site much more likely, increasing the resistivity of the system.”Resistance reaches a ceilingWhen the interactions between atoms became very strong, collision-driven resistivity no longer kept increasing. Instead, it reached a saturation point. The result suggests that resistance caused by electron scattering in metals may face a similar upper limit.“Our results provide a clear microscopic understanding of how resistivity works in low-density metals and open the door to new studies of strongly correlated atomic systems and quantum materials,” says Thywissen.Reference: “Lattice Unitarity: Saturated Collisional Resistivity in Hubbard Metals” by Frank Corapi, Robyn T. Learn, Benjamin Driesen, Antoine Lefebvre, Xavier Leyronas, Frédéric Chevy, Cora J. Fujiwara and Joseph H. Thywissen, 26 May 2026, Physical Review Letters. DOI: 10.1103/bhw8-p536Funding: Natural Sciences and Engineering Research Council of Canada, Agence Nationale de la Recherche, Institut Universitaire de FranceNever miss a breakthrough: Join the SciTechDaily newsletter.Follow us on Google and Google News.Condensed Matter Materials Science Quantum Materials Quantum Physics University of Toronto Scientists Create “Quantum Sound” Device That Works Near Absolute Zero A Strange Quantum Effect Could Power Future Electronics Without Batteries Physicists Finally Realize Long-Predicted 2D Topological Crystal in the Lab Puzzling Material Reveals Quantum Twist: Scientists Have Uncovered the True Nature of Bismuth A New Dimension of Quantum Materials: Topological Phonons Discovered in Crystal Lattices 40-Year Quantum Riddle Solved: Why Are “Strange Metals” So Strange?
Quantum Physicists Find Paradoxical Material a Mashup of Three Different Phases at Once – “This Is Uncharted Territory” Physicists Discover Strange New Magnetoelectric Effect Physicists Observe Quantum Criticality in a New Class of Materials Scientists May Have Discovered How To Heal Damaged Kidneys Interstellar Visitor 3I/ATLAS Is Bursting With an Unexpected Chemical Scientists Just Found All 5 Genetic “Letters” of DNA and RNA on an Asteroid The 4,000-Year-Old City That Defied History’s Rules on Wealth and Power The World’s Biggest Population Fear Has Flipped – and It Could Change Everything This “Fake” Pill Improved Memory and Physical Performance in Just 3 Weeks Scientists Say Frequent Ejaculation May Improve Sperm Quality and Fertility Scientists Have Found “The Heaven Sword” After Years of Looking