Elastic behavior of a two-dimensional crystal near melting.
Using positional data from video microscopy, we determine the elastic moduli of two-dimensional colloidal crystals as a function of temperature. The moduli are extracted from the wave-vector-dependent normal-mode spring constants in the limit q-->0 and are compared to the renormalized Young's modulus of the Kosterlitz-Thouless-Halperin-Nelson-Young theory. An essential element of this theory is the universal prediction that Young's modulus must approach 16 pi at the melting temperature. This is indeed observed in our experiment.
von Grünberg
H H
HH
Karl-Franzens-Universität, 8010 Graz, Austria.
Keim
P
P
Zahn
K
K
Maret
G
G