Piezomagnetic Material Changes Magnetic Properties When Stretched

NMR strain image
Top: A piece of BaFe2As2 is stretched while magnetic measurements are taken (the copper wire coil is part of the NMR device). Lower diagram shows atoms in a plane, with black arrows showing how magnetic spins lie in plane and point in opposite directions. Grey arrows show how the magnetic spin of atoms shifts as the material is stretched.

Piezoelectric materials, which generate an electric current when compressed or stretched, are familiar and widely used: think of lighters that spark when you press a switch, but also microphones, sensors, motors and all kinds of other devices. Now a group of physicists has found a material with a similar property, but for magnetism. This “piezomagnetic” material changes its magnetic properties when put under mechanical strain. Read more at UC Davis News.