Event DetailsEvent Dates: Wednesday, March 5, 2014 - 11:00amSeminar Location: JILA X317Speaker Name(s): Klaus Müller-DethlefsSpeaker Affiliation(s): The University of Manchester Seminar Type/SubjectScientific Seminar Type: JILA Public SeminarEvent Details & Abstract: Bose-Einstein Condensation (BEC) was first achieved in the liquid phase in helium a century and, for gas phase atoms, a decade ago. The question arises if there could be a third BEC in a solid, crystalline, state, as predicted by Lifshitz: the “Supersolid”. We are working on a possible pathway towards such a new state of matter: a /quantum plasma/ for which the electron /de Broglie/ wavelength becomes larger than the mean distance between particles, the Wigner-Seitz radius. For the electrons in an ultra-cold ion-electron plasma the electronic degeneracy condition is fulfilled for a temperature below 0.1/K/ and a density above 10^15 cm^3 . We produce such an ultra-cold Rydberg plasma by laser threshold ionization of NO molecules in the high-density expansion region of a supersonic jet close to the nozzle. This plasma has an extremely long lifetime of milliseconds and it shows the compressibility of a “sponge like” ultra-soft solid. An explanation of our experimental measurements is the formation of a /degenerate electron/ /fluid, /which should lead to the formation of a lattice of the cations, an /Abrikosov///Wigner/ ion crystal. Such a crystal would probably be far from perfect and exhibit a large number of defects. These crystal vacancies could then form a Bose-Einstein condensate producing a “Supersolid”.