Physics Experiment With Ultrafast Laser Pulses Produces A Previously Unseen Phase Of Matter
Arthur T Knackerbracket has found the following story:
Adding energy to any material, such as by heating it, almost always makes its structure less orderly. Ice, for example, with its crystalline structure, melts to become liquid water, with no order at all.
But in new experiments by physicists at MIT and elsewhere, the opposite happens: When a pattern called a charge density wave in a certain material is hit with a fast laser pulse, a whole new charge density wave is created-a highly ordered state, instead of the expected disorder. The surprising finding could help to reveal unseen properties in materials of all kinds.
The discovery is being reported today in the journal Nature Physics, in a paper by MIT professors Nuh Gedik and Pablo Jarillo-Herrero, postdoc Anshul Kogar, graduate student Alfred Zong, and 17 others at MIT, Harvard University, SLAC National Accelerator Laboratory, Stanford University, and Argonne National Laboratory.
The experiments made use of a material called lanthanum tritelluride, which naturally forms itself into a layered structure. In this material, a wavelike pattern of electrons in high- and low-density regions forms spontaneously but is confined to a single direction within the material. But when hit with an ultrafast burst of laser light-less than a picosecond long, or under one trillionth of a second-that pattern, called a charge density wave or CDW, is obliterated, and a new CDW, at right angles to the original, pops into existence.
Read more of this story at SoylentNews.