August 12, 2013

Physicists of Mainz University investigate the formation of defects during phase transitions in crystals of ions



Recent research findings are relevant to a model of matter structure formation tiny fractions of a second after the Big Bang

Research groups at Johannes Gutenberg University Mainz (JGU) and the Physical-Technical Federal Institute (PTB) in Braunschweig, working in collaboration with scientists at the University of Ulm and The Hebrew University of Jerusalem, have been investigating the formation of defects occurring when a Coulomb crystal of ions is driven through a second-order phase transition. For this purpose, they compressed one-dimensional linear chains of ions at high speeds to form a two-dimensional zigzag structure with a form similar to that of an accordion. This process can lead to the generation of defects in the resultant crystal structure. The probability of such defects forming is determined by the speed of the phase transition. The Kibble-Zurek mechanism, which describes the formation of such defects, is universal as it plays an important role in many physical systems. Among other things, this mechanism is the basis of one theory of how matter was created 10-30 seconds after the Big Bang. The experiments undertaken in Mainz investigated and analyzed this effect with a hitherto unrivalled precision.