Showing posts from December 2, 2014

New State of matter : Dropletons

There was a time when states of matter were simple: Solid, liquid, gas. Then came plasma, Bose -Einstein condensate, supercritical fluid and more. Now the list has grown by one more, with the unexpected discovery of a new state dubbed “dropletons” that bear some resemblance to liquids but occur under very different circumstances. The discovery occurred when a team at the University of Colorado Joint Institute for Lab Astrophysics were focusing laser light on gallium arsenide (GaAs) to create excitons. Excitons are formed when a photon strikes a material, particularly a semiconductor. If an electron is knocked loose, or excited, it leaves what is termed an “electron hole” behind. If the forces of other charges nearby keep the electron close enough to the hole to feel an attraction, a bound state forms known as an exciton. Excitons are called quasiparticles because the electrons and holes behave together as if they were a single particle.

If this all sounds a bit hard to re…