Carnegie Mellon University scientists have uncovered a new phenomenon that challenges a longstanding assumption about how electronic materials respond to magnetic fields. The discovery broadens the fundamental understanding of the Hall effect, a principle widely used to measure the magnetic and electronic properties of materials.

Published in Nature Materials, the research could lay the groundwork for simpler, more versatile magnetic sensing technologies used in electronics, transportation and medical imaging.

The Hall effect has been a key tool for studying material properties for more than a century. In 1879, Edwin Hall showed that applying a magnetic field perpendicular to a material deflects moving charges, producing a measurable voltage. By analyzing this signal, scientists can determine whether electric current is carried by negative or positive charges, how many of those charges are moving through the material and how easily they flow.