Researchers use laser light to transform metal into magnet

Phys.org  September 16, 2019
Up to now, researchers have only been capable of manipulating the properties already found in a material using light. An international team of researchers (Denmark, Singapore) has shown that when the material is irradiated with laser light, plasmons in the metal disk begin to rotate in either a clockwise or counterclockwise direction. However, these plasmons change the quantum electronic structure of a material, which simultaneously alters their own behavior, catalyzing a feedback loop. Feedback from the plasmons’ internal electric fields eventually causes the plasmons to break the intrinsic symmetry of the material and trigger an instability toward self-rotation that causes the metal to become magnetic. The principle could be useful in situations where one needs a material to alternate between behaving magnetically and not. It could also prove useful in opto-electronics—where, for example, light and electronics are combined for fiber-internet and sensor development…read more. TECHNICAL ARTICLE