Frankfurt 2006 – scientific programme
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MO: Molekülphysik
MO 14: Ultrafast IR and Raman Probe and Control
MO 14.1: Talk
Monday, March 13, 2006, 16:30–16:45, H12
Bulk ice at room temperature — •Marcus Schmeisser, Hristo Iglev, and Alfred Laubereau — Technische Universität München, Physik-Department E11, James-Franck-Straße, 85748 Garching
The complex three-dimensional hydrogen-bonded network of water molecules gives rise to unusual solid and liquid properties and strongly affects the melting behaviour of ice. Here we present the first experimental evidence for ultrafast superheating of bulk ice using an ultrafast temperature-jump technique with subpicosecond pulses for excitation and probing in the mid-infrared. The hydroxilic stretching vibrations (OH or OD) of isotopically mixed ice are used for energy deposition and for the fast and sensitive spectral probing of local temperature and H-bonding environment.
Measurements performed for a HDO:D2O specimen with initial temperature of 270 K (close to the melting point of 274.8 K) provide evidence for substantial superheating of the ice lattice up to 301±2 K that persists over the monitored time interval of 250 ps without melting [1,2]. For higher pumping levels evidence for ultrafast melting of bulk ice is obtained [1].
[1] H. Iglev, M. Schmeisser, K. Simeonidis, A. Thaller und A. Laubereau, Nature (2006), in press.
[2] H. Iglev, M. Schmeisser, A. Thaller und A. Laubereau, subm.