Wolf, Dietrich; Villain, Jacques:

Shape fluctuations of crystal bars

In: Physical review B, Jg. 41 (1990) ; Nr. 4, S. 2434-2444
ISSN: 1098-0121
Zeitschriftenaufsatz / Fach: Physik
In the standard theory of the equilibrium shape of a crystal {Wulff construction), thermal fluctuations
are neglected. In the present work their effect is investigated in the simple case of a bar with
four symmetric facets. The edges of the facets are found to undergo fluctuations with a correlation
length proportional to the width 2R of the facets, which is itself proportional to the diameter of the
bar. The amplitude of these fluctuations decays exponentially beyond a range proportional to R ' '.
It is therefore legitimate to neglect them for large crystals. The stability of the bar is also considered:
The decay into crystallites is very slow with a characteristic time increasing exponentially
with R.