TY - JOUR
T1 - Long-wavelength fluctuations and dimensionality crossover in confined liquids
AU - Yang, Jing
AU - Li, Yan Wei
AU - Ciamarra, Massimo Pica
N1 - Publisher Copyright:
© 2021 authors. Published by the American Physical Society.
PY - 2021/9
Y1 - 2021/9
N2 - The phase behavior of liquids confined in a slit geometry does not reveal a crossover from a three- to a two-dimensional behavior as the gap size decreases. Indeed, the prototypical two-dimensional hexatic phase only occurs in liquids confined to a monolayer. Here, we demonstrate that the dimensionality crossover is apparent in the lateral size dependence of the relaxation dynamics of confined liquids, developing a Debye model for the density of vibrational states of confined systems and performing extensive numerical simulations. In confined systems, Mermin-Wagner fluctuations enhance the amplitude of vibrational motion - or the Debye-Waller factor - by a quantity scaling as the inverse gap width and proportional to the logarithm of the aspect ratio, as a clear signature of a two-dimensional behavior. As the temperature or lateral system size increases, the crossover to a size-independent relaxation dynamics occurs when structural relaxation takes place before the vibrational modes with the longest wavelength develop.
AB - The phase behavior of liquids confined in a slit geometry does not reveal a crossover from a three- to a two-dimensional behavior as the gap size decreases. Indeed, the prototypical two-dimensional hexatic phase only occurs in liquids confined to a monolayer. Here, we demonstrate that the dimensionality crossover is apparent in the lateral size dependence of the relaxation dynamics of confined liquids, developing a Debye model for the density of vibrational states of confined systems and performing extensive numerical simulations. In confined systems, Mermin-Wagner fluctuations enhance the amplitude of vibrational motion - or the Debye-Waller factor - by a quantity scaling as the inverse gap width and proportional to the logarithm of the aspect ratio, as a clear signature of a two-dimensional behavior. As the temperature or lateral system size increases, the crossover to a size-independent relaxation dynamics occurs when structural relaxation takes place before the vibrational modes with the longest wavelength develop.
UR - http://www.scopus.com/inward/record.url?scp=85115889668&partnerID=8YFLogxK
U2 - 10.1103/PhysRevResearch.3.033172
DO - 10.1103/PhysRevResearch.3.033172
M3 - Article
AN - SCOPUS:85115889668
SN - 2643-1564
VL - 3
JO - Physical Review Research
JF - Physical Review Research
IS - 3
M1 - 033172
ER -