1302.5343 (S. Ulm et al.)

Observation of the Kibble-Zurek scaling law for defect formation in ion
crystals    [PDF]

S. Ulm, J. Roßnagel, G. Jacob, C. Degünther, S. T. Dawkins, U. G. Poschinger, R. Nigmatullin, A. Retzker, M. B. Plenio, F. Schmidt-Kaler, K. Singer

Traversal of a symmetry-breaking phase transition at a finite rate can lead to causallyseparated regions with incompatible symmetries and the formation of defects at their boundaries. The defect formation follows universal scaling laws prescribed by the Kibble-Zurek mechanism (KZM) important to the study of phase transitions in fields as diverse as quantum and statistical mechanics, condensed matter physics and cosmology. Here, we observe the KZM in a crystal of cold trapped ions, which is conducive to the precise control of structural phases and the detection of defects. The experiment confirms a scaling law with an exponent of 2.68 +/- 0.06, as predicted from the KZM in the finite inhomogeneous case. Such precision makes it feasible to use ion crystals for quantitative tests of classical and quantum statistical mechanics.

View original: http://arxiv.org/abs/1302.5343