Abstract

Static electricity—or more scientifically, contact electrification—remains one of the oldest and hardest problems in all of the physical sciences. When two materials touch and separate, they exchange electrical charge, yet we are more or less clueless as to why. This effect has been recognized since the ancient world and plays a crucial role in natural phenomena ranging from sandstorm electrification in the world’s great deserts, to the transport of aerosols across oceans and continents, and perhaps even rocky planet formation. In addition to this, it is also a primary concern in virtually all the world's industries, where charge buildup can cause disruptions and even deadly explosions in settings ranging from mines to oil rigs. In my group, we study an even trickier aspect of this contact electrification: the charge exchange that occurs when identical materials touch, which occurs robustly despite the absence of any obvious symmetry-breaking parameter. In this talk, I will discuss our work with identical oxide materials, which presents a number of challenges. First, these materials are extremely hard, which means their contact areas—and hence charge exchange—are extremely small. Second, we cannot touch them ourselves when we handle them, or we will add superfluous charge that overrides what we are trying to measure. We overcome these challenges with a world-unique platform we have developed using acoustic levitation. This approach allows us to perform thousands of automated and hands-free contacts and measure charge with a few-hundred-electron resolution on macroscopic samples. Our experiments have led to the discovery that the symmetry breaker in oxide contact electrification lies in surface adsorbates, not the bulk material. These results, currently accepted at Nature, prime the field for a long-sought mechanistic understanding of the effect, with relevance to situations ranging from desert sandstorms to industrial power plants.

Biography

Scott Waitukaitis is an experimental physicist and Assistant Professor at the Institute of Science and Technology Austria (ISTA). He received his PhD in Physics from the University of Chicago, where he was the recipient of the Robert Millikan Fellowship. His research lies at the intersection of soft matter physics and electrostatics, with a particular focus on contact electrification, tribocharging, and electrically active soft materials. He is internationally recognized for developing novel experimental platforms—most notably with acoustic and optical levitation techniques—that enable precise, contact-free measurements of charge transfer at the single-particle and even single-electron level. His work has led to fundamental advances in understanding charge exchange in oxides and polymers, leading to publications in Nature, Nature Physics, PNAS, and Physical Review Letters.

He is the recipient of the 2026 APS Early Career Award for Soft Matter Research, the Springer Thesis Prize, the Block Prize for Outstanding Young Researcher, the Fysica Young Speaker's Award, and the CJ Kok Discoverer of the Year Award. He is a member of the Young Academy of the Austrian Academy of Sciences.

His research has been supported by major competitive funding, including an ERC Starting Grant, a Marie Skłodowska-Curie Doctoral Networks Grant, and a Veni Grant from the Netherlands Organisation for Scientific Research.