Related Experiment Videos
Dynamic phases in the two-dimensional underdamped driven Frenkel-Kontorova model
Jasmina Tekić1, O M Braun, Bambi Hu
1Department of Physics, Centre for Nonlinear Studies, The Beijing-Hong Kong-Singapore Joint Centre for Nonlinear and Complex Systems (Hong Kong), Hong Kong Baptist University, Hong Kong, China.
Summary
We investigated how driven atomic layers transition from disordered to ordered states. Different damping and stiffness values create unique intermediate phases like traffic jams or plastic channels during this crystal sliding transition.
Area of Science:
- Condensed matter physics
- Nonlinear dynamics
- Materials science
Background:
- Studying the behavior of driven systems is crucial for understanding phenomena like friction and material transport.
- Two-dimensional (2D) systems offer unique properties due to reduced dimensionality.
- Underdamped systems exhibit rich dynamics influenced by inertia and dissipation.
Purpose of the Study:
- To explore the nonlinear direct current (dc) response of a 2D underdamped system of interacting atoms.
- To investigate the transition from a disordered to an ordered sliding state under an increasing driving force.
- To characterize intermediate phases and dynamic regimes during the ordering transition by varying system parameters.
Main Methods:
- Simulating a 2D system of interacting atoms subjected to a periodic external potential with triangular symmetry.
- Analyzing the system's response to a nonlinear dc driving force.
- Varying key parameters: effective elastic constant, damping coefficient, and temperature.
Main Results:
- The system transitions from a disorder-locked state to an ordered sliding state (moving crystal) as the driving force increases.
- Different intermediate phases and scenarios were observed by tuning the elastic constant, damping, and temperature.
- For soft layers, a plastic-channel regime emerges at higher damping.
- For stiff layers, a traffic-jam regime with immobile islands occurs at high elastic constants.
- Soliton-like elastic flow was observed in stiff layers under high driving forces.
Conclusions:
- The nonlinear response of driven 2D atomic systems is complex and highly dependent on system parameters.
- Intermediate phases, such as plastic channels and traffic jams, significantly influence the overall ordering transition.
- Understanding these regimes is key to controlling and predicting the behavior of materials under external forces.