A new form of matter: Excitonium

• Researchers at the University of Illinois have announced the existence of a new form of matter called excitonium.

• This material is made up of a kind of boson, a composite particle that could allow the matter to act as a superfluid, superconductor, or even as an insulating electronic crystal.

• The hole is positively charged and the electron is negatively charged, so it is possible to create a bound state between the two, with the electron orbiting the hole, instead of falling back in. This bound state is the exciton, which is the building block of excitonium.

• There are five known states of matter: solids, liquids, gases, plasma and Bose-Einstein condensates.