1 research outputs found
Mermin-Wagner fluctuations in 2D amorphous solids
In a recent comment, M. Kosterlitz described how the discrepancy about the
lack of broken translational symmetry in two dimensions - doubting the
existence of 2D crystals - and the first computer simulations foretelling 2D
crystals at least in tiny systems, motivated him and D. Thouless to investigate
melting and suprafluidity in two dimensions [Jour. of Phys. Cond. Matt.
\textbf{28}, 481001 (2016)]. The lack of broken symmetries proposed by D.
Mermin and H. Wagner is caused by long wavelength density fluctuations. Those
fluctuations do not only have structural impact but additionally a dynamical
one: They cause the Lindemann criterion to fail in 2D and the mean squared
displacement not to be limited. Comparing experimental data from 3D and 2D
amorphous solids with 2D crystals we disentangle Mermin-Wagner fluctuations
from glassy structural relaxations. Furthermore we can demonstrate with
computer simulations the logarithmic increase of displacements predicted by
Mermin and Wagner: periodicity is not a requirement for Mermin-Wagner
fluctuations which conserve the homogeneity of space on long scales.Comment: 7 pages, 4 figure