Nonlinear driven response of a phase-field crystal in a periodic pinning potential
| Autor: | Enzo Granato, Mikko Karttunen, C. V. Achim, J. A. P. Ramos, Tapio Ala-Nissila, Ken Elder, See-Chen Ying |
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| Přispěvatelé: | Perustieteiden korkeakoulu, School of Science, Teknillisen fysiikan laitos, Department of Applied Physics, Aalto-yliopisto, Aalto University |
| Jazyk: | angličtina |
| Rok vydání: | 2009 |
| Předmět: |
Physics
Condensed Matter - Materials Science Continuous density Condensed matter physics Phase field crystal Crystal system Materials Science (cond-mat.mtrl-sci) FOS: Physical sciences C-I transitions Condensed Matter - Soft Condensed Matter 01 natural sciences 010305 fluids & plasmas Nonlinear system Transverse plane Classical mechanics Lattice (order) Condensed Matter::Superconductivity 0103 physical sciences Soft Condensed Matter (cond-mat.soft) 010306 general physics Pinning force pinned lattices nonlinear driven response Phase diagram |
| Zdroj: | Physical Review E-Statistical, Nonlinear, and Soft Matter Physics, 79(1), 011606-1/10. American Physical Society |
| ISSN: | 1539-3755 |
| Popis: | We study numerically the phase diagram and the response under a driving force of the phase field crystal model for pinned lattice systems introduced recently for both one- and two-dimensional systems. The model describes the lattice system as a continuous density field in the presence of a periodic pinning potential, allowing for both elastic and plastic deformations of the lattice. We first present results for phase diagrams of the model in the absence of a driving force. The nonlinear response to a driving force on an initially pinned commensurate phase is then studied via overdamped dynamic equations of motion for different values of mismatch and pinning strengths. For large pinning strength the driven depinning transitions are continuous, and the sliding velocity varies with the force from the threshold with power-law exponents in agreement with analytical predictions. Transverse depinning transitions in the moving state are also found in two dimensions. Surprisingly, for sufficiently weak pinning potential we find a discontinuous depinning transition with hysteresis even in one dimension under overdamped dynamics. We also characterize structural changes of the system in some detail close to the depinning transition. |
| Databáze: | OpenAIRE |
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