Hysteresis in the pinning-depinning transition in underdamped two-dimensional Frenkel-Kontorova model

¹ Department of Physics, Northwest Normal University - Lanzhou, 730070, PRC
² State Key Laboratory of Solid Lubrication, Lanzhou Institute of Chemical Physics, Chinese Academy of Science Lanzhou, 730000, PRC

^a duanws@126.com

Received: 12 March 2011
Accepted: 21 April 2011

Abstract

Hysteretic phenomenon is studied in the 2D Frenkel-Kontorova model system. In the depinning process, two critical points F_s1 and F_s2 are found. In the pinning process, two critical points F_b1 and F_b2 are also found. The dependence of four critical forces F_s1, F_s2, F_b1, F_b2 on the system parameters such as external driving force, misfit angle, winding number, interatomic strength is investigated. The winding number b/a substantially affect the depinning forces of F_s1 and F_s2, but not the pinning forces of both F_b1 and F_b2. The pinning force of F_b2 linearly increases as the interatomic interaction strength (K) increase. The dependence of both F_b1 and F_b2 on the misfit angle θ is not in fractal structure which is different from the depinning force of F_s1.