The Physics of Snowflakes: A Close Look at the Real Origins
Kenneth G. Libbrecht
This talk will examine the growth of ice crystals from the vapor phase, focusing on the non-equilibrium dynamical processes that govern crystal growth in general. Ice is particularly interesting because the growth rates of both the basal and prism facets vary strongly and non-monotonically with temperature. Much of this behavior is thought to be related to the onset of surface melting at approximately -15C, although many theoretical uncertainties remain. In addition to normal growth, we have also been examining the effects of strong electric fields on diffusion-limited needle crystal growth, again using ice as a case study. Both theory and experiments reveal the onset of an unusual growth instability at high voltages, leading to the rapid growth of thin needle crystals.