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, Nomi
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  - Cuzzi, Jeff N.
A1  - Burns, Joseph A.
A1  - Charnoz, Sébastien
A1  - Clark, Roger N.
A1  - Colwell, Josh E.
A1  - Dones, Luke
A1  - Esposito, Larry W.
A1  - Filacchione, Gianrico
A1  - French, Richard G.
A1  - Hedman, Matthew M.
A1  - Kempf, Sascha
A1  - Marouf, Essam A.
A1  - Murray, Carl D.
A1  - Nicholson, Phillip D.
A1  - Porco, Carolyn C.
A1  - Schmidt, Jürgen
A1  - Showalter, Mark R.
A1  - Spilker, Linda J.
A1  - Spitale, Joseph N.
A1  - Srama, Ralf
A1  - Sremcević, Miodrag
A1  - Tiscareno, Matthew Steven
A1  - Weiss, John
T1  - An evolving view of Saturn's dynamic rings
N2  - We review our understanding of Saturn's rings after nearly 6 years of observations by the Cassini spacecraft. Saturn's rings are composed mostly of water ice but also contain an undetermined reddish contaminant. The rings exhibit a range of structure across many spatial scales; some of this involves the interplay of the fluid nature and the self-gravity of innumerable orbiting centimeter- to meter-sized particles, and the effects of several peripheral and embedded moonlets, but much remains unexplained. A few aspects of ring structure change on time scales as short as days. It remains unclear whether the vigorous evolutionary processes to which the rings are subject imply a much younger age than that of the solar system. Processes on view at Saturn have parallels in circumstellar disks.
Y1  - 2010
UR  - http://www.sciencemag.org/
U6  - https://doi.org/10.1126/science.1179118
SN  - 0036-8075
ER  -