Libbrecht, Kenneth G. and Tanusheva, Victoria M. (1999) Cloud chambers and crystal growth: Effects of electrically enhanced diffusion on dendrite formation from neutral molecules. Physical Review E, 59 (3). pp. 3253-3261. ISSN 1063-651X. http://resolver.caltech.edu/CaltechAUTHORS:LIBpre99b
See Usage Policy.
Use this Persistent URL to link to this item: http://resolver.caltech.edu/CaltechAUTHORS:LIBpre99b
We present an extension of the solvability theory for free dendrite growth that includes the effects of electrically enhanced diffusion of neutral polar molecules. Our theory reveals a new instability mechanism in free dendrite growth, which arises when electrically enhanced diffusion near the dendrite tip overwhelms the stabilizing influence of surface tension. This phenomenon is closely related to the growth instability responsible for the visualization of charged particle tracks in cloud chambers, and is expected for enhanced diffusion of neutral molecules, but not for the case of ionic diffusion. Above a threshold applied potential, the crystal growth can no longer be described by the usual solvability theory, and requires a new physical mechanism to limit the growth velocity. We also describe experimental observations of the free dendrite growth of ice crystals from water vapor in supersaturated normal air. These observations demonstrate the calculated growth instability, which results in the rapid growth of branchless ice needles with a tip velocity 5–50 times the normal dendrite tip velocity. The production of clean ice needles is useful for the study of ice crystal growth from vapor, allowing the controlled growth of isolated single-crystal samples. This instability mechanism may find further application in crystal growth from a wide variety of polar molecules.
|Additional Information:||©1999 The American Physical Society Received 14 October 1998 The authors acknowledge support for V.M.T. by Mr. and Mrs. Downie D. Muir III.|
|Usage Policy:||No commercial reproduction, distribution, display or performance rights in this work are provided.|
|Deposited By:||Archive Administrator|
|Deposited On:||19 Dec 2006|
|Last Modified:||26 Dec 2012 09:24|
Repository Staff Only: item control page