Die u:cris Detailansicht:
Experimental observation of defect pair separation triggering phase transitions
- Autor(en)
- M. Cordin, B. A. J. Lechner, S. Duerrbeck, A. Menzel, E. Bertel, J. Redinger, C. Franchini
- Abstrakt
First-order phase transitions typically exhibit a significant hysteresis resulting for instance in boiling retardation and supercooling. The hysteresis arises, because nucleation of the new phase is activated. The free-energy change is positive until the nucleus reaches a critical size beyond which further growth is downhill. In practice, the barrier is often circumvented by the presence of heterogeneous nucleation centres, e. g. at vessel walls or seed crystals. Recently, it has been proposed that the homogeneous melting of ice proceeds via separation of defect pairs with a substantially smaller barrier as compared to the mere aggregation of defects. Here we report the observation of an analogous mechanism catalysing a two-dimensional homogeneous phase transition. A similar process is believed to occur in spin systems. This suggests that separation of defect pairs is a common trigger for phase transitions. Partially circumventing the activation barrier it reduces the hysteresis and may promote fluctuations within a temperature range increasing with decreasing dimensionality.
- Organisation(en)
- Computergestützte Materialphysik
- Externe Organisation(en)
- Leopold-Franzens-Universität Innsbruck, Technische Universität Wien
- Journal
- Scientific Reports
- Band
- 4
- Anzahl der Seiten
- 4
- ISSN
- 2045-2322
- DOI
- https://doi.org/10.1038/srep04110
- Publikationsdatum
- 03-2014
- Peer-reviewed
- Ja
- ÖFOS 2012
- 103009 Festkörperphysik, 103015 Kondensierte Materie, 103025 Quantenmechanik, 103036 Theoretische Physik
- Schlagwörter
- Link zum Portal
- https://ucrisportal.univie.ac.at/de/publications/0cac27cf-2afe-4b28-99e8-311abec0a4eb