TY - JOUR A1 - de Jong, S. A1 - Kukreja, R. A1 - Trabant, C. A1 - Pontius, N. A1 - Chang, C. F. A1 - Kachel, T. A1 - Beye, Martin A1 - Sorgenfrei, Florian A1 - Back, C. H. A1 - Braeuer, B. A1 - Schlotter, W. F. A1 - Turner, J. J. A1 - Krupin, O. A1 - Doehler, M. A1 - Zhu, D. A1 - Hossain, M. A. A1 - Scherz, A. O. A1 - Fausti, D. A1 - Novelli, F. A1 - Esposito, M. A1 - Lee, W. S. A1 - Chuang, Y. D. A1 - Lu, D. H. A1 - Moore, R. G. A1 - Yi, M. A1 - Trigo, M. A1 - Kirchmann, P. A1 - Pathey, L. A1 - Golden, M. S. A1 - Buchholz, Marcel A1 - Metcalf, P. A1 - Parmigiani, F. A1 - Wurth, W. A1 - Föhlisch, Alexander A1 - Schuessler-Langeheine, Christian A1 - Duerr, H. A. T1 - Speed limit of the insulator-metal transition in magnetite JF - Nature materials N2 - As the oldest known magnetic material, magnetite (Fe3O4) has fascinated mankind for millennia. As the first oxide in which a relationship between electrical conductivity and fluctuating/localized electronic order was shown(1), magnetite represents a model system for understanding correlated oxides in general. Nevertheless, the exact mechanism of the insulator-metal, or Verwey, transition has long remained inaccessible(2-8). Recently, three- Fe- site lattice distortions called trimeronswere identified as the characteristic building blocks of the low-temperature insulating electronically ordered phase(9). Here we investigate the Verwey transition with pump- probe X- ray diffraction and optical reflectivity techniques, and show how trimerons become mobile across the insulator-metal transition. We find this to be a two- step process. After an initial 300 fs destruction of individual trimerons, phase separation occurs on a 1.5 +/- 0.2 ps timescale to yield residual insulating and metallic regions. This work establishes the speed limit for switching in future oxide electronics(10). Y1 - 2013 U6 - https://doi.org/10.1038/NMAT3718 SN - 1476-1122 SN - 1476-4660 VL - 12 IS - 10 SP - 882 EP - 886 PB - Nature Publ. Group CY - London ER - TY - JOUR A1 - Braeuer, B. A1 - Asch, Günter A1 - Hofstetter, Rami A1 - Haberland, Christian A1 - Jaser, Darweesh A1 - El-Kelani, Radwan J.. A1 - Weber, Michael H. T1 - Microseismicity distribution in the southern Dead Sea basin and its implications on the structure of the basin JF - Geophysical journal international N2 - While the Dead Sea basin has been studied for a long time, the available knowledge about the detailed seismicity distribution in the area, as well as the deeper structure of the basin, is limited. Therefore, within the framework of the international project DESIRE (DEad Sea Integrated REsearch project), a dense temporary local seismological network was operated in the southern Dead Sea area. We use 530 local earthquakes, having all together 26 730 P- and S-arrival times for a simultaneous inversion of 1-D velocity models, station corrections and precise earthquake locations. Jackknife tests suggest an accuracy of the derived hypocentre locations of about 1 km. Thus, the result is the first clear image of the absolute distribution of the microseismicity of the area, especially in depth. The seismicity is concentrated in the upper crust down to 20 km depth while the lower limit of the seismicity is reached at 31 km depth. The seismic events at the eastern boundary fault (EBF) in the southern part of the study area represent the northward transform motion of the Arabian Plate along the Dead Sea Transform. North of the Boqeq fault the seismic activity represents the transfer of the motion in the pull-apart basin from the eastern to the western boundary. We find that from the surface downward the seismic events are tracing the boundary faults of the basin. The western boundary is mapped down to 12 km depth while the EBF reaches about 17 km depth, forming an asymmetric basin. One fifth of the data set is related to a specific cluster in time and space, which occurred in 2007 February at the western border fault. This cluster is aligned vertically, that is, it is perpendicular to the direction of the dominating left-lateral strike-slip movement at the main transform fault. KW - Seismicity and tectonics KW - Continental tectonics: strike-slip and transform KW - Asia Y1 - 2012 U6 - https://doi.org/10.1111/j.1365-246X.2011.05318.x SN - 0956-540X VL - 188 IS - 3 SP - 873 EP - 878 PB - Wiley-Blackwell CY - Malden ER -