Solidification Velocities in Deeply Undercooled Silver
Abstract
We measure the solidification velocity of pure Ag as a function of undercooling temperature from the melting point (Tm=1235K) to 0.6Tm using ultrafast, pump-probe laser experiments. The thickness of the liquid layer, while it solidifies, is measured using optical third harmonic generation. We show that velocity reaches a maximum value at 0.85Tm, and then remains nearly constant with additional undercooling. These results contradict simple collision-limited models, but they are in good agreement with molecular dynamics simulations presented here, which show that the crystallization velocity depends weakly on temperature from 0.85Tm to less than ≈0.1Tm.
- Publication:
-
Physical Review Letters
- Pub Date:
- March 2009
- DOI:
- 10.1103/PhysRevLett.102.095701
- Bibcode:
- 2009PhRvL.102i5701C
- Keywords:
-
- 64.70.D-;
- 61.20.Lc;
- 61.80.Ba;
- 81.30.Fb;
- Solid-liquid transitions;
- Time-dependent properties;
- relaxation;
- Ultraviolet visible and infrared radiation effects;
- Solidification