Nonlinear driven response of a phase-field crystal in a periodic pinning potential

Tutkimustuotos: Lehtiartikkelivertaisarvioitu

Tutkijat

  • Cristian V. Achim
  • Jorge Ramos
  • Mikko Karttunen
  • Ken Elder
  • Enzo Granato
  • Tapio Ala-Nissilä

  • See-Chen Ying

Organisaatiot

Kuvaus

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.

Yksityiskohdat

AlkuperäiskieliEnglanti
Artikkeli011606
Sivut1-10
JulkaisuPhysical Review E
Vuosikerta79
Numero1
TilaJulkaistu - 2009
OKM-julkaisutyyppiA1 Julkaistu artikkeli, soviteltu

    Tutkimusalat

  • C-I transitions, nonlinear driven response, pinned lattices

ID: 3399052