TY - JOUR
T1 - Unveiling Dimensionality Dependence of Glassy Dynamics
T2 - 2D Infinite Fluctuation Eclipses Inherent Structural Relaxation
AU - Shiba, Hayato
AU - Yamada, Yasunori
AU - Kawasaki, Takeshi
AU - Kim, Kang
N1 - Funding Information:
This work was partially supported by JSPS KAKENHI Grants No.JP25103010 (H.S.), No.JP15H06263 and No.JP16H06018 (T.K.), and No.JP26400428 and No.JP16H00829 (K.K.). H.S. and Y.Y. were also financially supported by the Building of Consortia for the Development of Human Resources in Science and Technology, Ministry of Education, Culture, Sports, Science, and Tehnology (MEXT), Japan. The numerical calculations were carried out on SGI Altix ICE 8400EX and XA at Institute for Solid State Physics (ISSP), University of Tokyo and on Fujitsu PRIMERGY RX300 S7 at Research Center for Computational Science (RCCS), Okazaki, Japan.
Publisher Copyright:
© 2016 American Physical Society.
PY - 2016/12/7
Y1 - 2016/12/7
N2 - By using large-scale molecular dynamics simulations, the dynamics of two-dimensional (2D) supercooled liquids turns out to be dependent on the system size, while the size dependence is not pronounced in three-dimensional (3D) systems. It is demonstrated that the strong system-size effect in 2D amorphous systems originates from the enhanced fluctuations at long wavelengths which are similar to those of 2D crystal phonons. This observation is further supported by the frequency dependence of the vibrational density of states, consisting of the Debye approximation in the low-wave-number limit. However, the system-size effect in the intermediate scattering function becomes negligible when the length scale is larger than the vibrational amplitude. This suggests that the finite-size effect in a 2D system is transient and also that the structural relaxation itself is not fundamentally different from that in a 3D system. In fact, the dynamic correlation lengths estimated from the bond-breakage function, which do not suffer from those enhanced fluctuations, are not size dependent in either 2D or 3D systems.
AB - By using large-scale molecular dynamics simulations, the dynamics of two-dimensional (2D) supercooled liquids turns out to be dependent on the system size, while the size dependence is not pronounced in three-dimensional (3D) systems. It is demonstrated that the strong system-size effect in 2D amorphous systems originates from the enhanced fluctuations at long wavelengths which are similar to those of 2D crystal phonons. This observation is further supported by the frequency dependence of the vibrational density of states, consisting of the Debye approximation in the low-wave-number limit. However, the system-size effect in the intermediate scattering function becomes negligible when the length scale is larger than the vibrational amplitude. This suggests that the finite-size effect in a 2D system is transient and also that the structural relaxation itself is not fundamentally different from that in a 3D system. In fact, the dynamic correlation lengths estimated from the bond-breakage function, which do not suffer from those enhanced fluctuations, are not size dependent in either 2D or 3D systems.
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U2 - 10.1103/PhysRevLett.117.245701
DO - 10.1103/PhysRevLett.117.245701
M3 - Article
AN - SCOPUS:85003467462
SN - 0031-9007
VL - 117
JO - Physical Review Letters
JF - Physical Review Letters
IS - 24
M1 - 245701
ER -