24 Jul New probing technique maps properties in quantum materials
Dr. Ying Wang
University of Wisconsin-Madison engineers have developed a new technique to map the quantum phase diagram in a promising class of quantum materials called Weyl semimetals by tracking “hotspots” in an unusual quantum phenomenon called the nonlinear Hall effect.
The technique, based on a unique quantum geometry signature, enables scientists to identify phase transitions in topological materials and determine whether these transitions are linked to deeper changes in the material’s topological properties. This insight could accelerate the discovery of exotic quantum phases and help identify materials with optimal electronic characteristics for building next-generation low-power, high-efficiency electronics and optoelectronic devices.
The research, led by Ying Wang, an assistant professor in electrical and computer engineering at UW-Madison, appeared July 10, 2025, in the journal Nature Communications. Daniel Rhodes and Jun Xiao, assistant professors in materials science and engineering at UW-Madison, collaborated on the research.
Topological materials are a class of quantum materials whose electronic behavior is governed not only by local atomic arrangements but also by global topological properties of their quantum wavefunctions. Unlike conventional materials (insulators, metals, and semiconductors), electrons in topological materials flow along the surface and edges of a material and will maintain their movement pattern despite any twists, turns or other obstructions they may encounter. Over the last two decades, researchers have begun engineering topological materials for use in robust and low-power electronics and even topological quantum computing.