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Interactive Molecular Model Assembly with 3D Printing
Published on: August 13, 2020
Driven kink in the frenkel-kontorova model
1Institute of Physics, National Ukrainian Academy of Sciences, 03650 Kiev, Ukraine and Department of Physics and CNS, Hong Kong Baptist University, Hong Kong, China.
Summary
High-velocity kinks in atomic chains become unstable, decaying into kink-antikink pairs. These pairs then transition the chain to a free-running state, with atoms sliding over the potential.
Area of Science:
- Condensed Matter Physics
- Nonlinear Dynamics
- Statistical Mechanics
Background:
- The Frenkel-Kontorova model describes interacting atoms in a periodic potential.
- Topological solitons (kinks) are stable excitations in such systems.
- Understanding kink dynamics is crucial for solid-state physics and materials science.
Purpose of the Study:
- To investigate the dynamics of dc-driven atomic chains.
- To analyze the stability of topological solitons at high velocities.
- To elucidate the mechanisms of energy dissipation and phase transitions in these systems.
Main Methods:
- Numerical simulations of the discrete Frenkel-Kontorova model.
- Analysis of kink velocity and stability.
- Identification and characterization of localized modes (discrete breathers).
Main Results:
- In the underdamped regime, high-velocity kinks become unstable.
- Instability arises from the excitation of discrete breathers in the kink's tail.
- Breather decay leads to kink-antikink pair creation and subsequent chain transition to a free-running state.
Conclusions:
- The study reveals a novel instability mechanism for topological solitons.
- Discrete breathers play a critical role in mediating kink decay and energy transfer.
- The findings offer insights into nonlinear phenomena and phase transitions in discrete systems.
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