Carnegie Mellon University researchers have identified an unusual magnetic response that overturns a long-standing assumption about the Hall effect, a foundational principle used to study how materials behave electrically and magnetically.
The findings, published in Nature Materials, expand scientists' understanding of the Hall effect and could eventually support simpler and more flexible magnetic sensors for electronics, transportation and medical imaging.
Rethinking a Century-Old Physics Effect
Scientists have relied on the Hall effect for more than a century. In 1879, Edwin Hall discovered that when a magnetic field is applied perpendicular to a material carrying an electric current, the moving charges are pushed to one side. This creates a voltage that researchers can measure.
That signal reveals important information about a material, including whether its current is carried by positive or negative charges, how many charge carriers are present, and how easily they can move. Hall effect sensors are now widely used in technologies ranging from cars to computer keyboards.
