Influence of the bond defect in driven Frenkel-Kontorova chains

Abstract

We study the influence of a bond defect in a nonlinear coupled pendulum chain subjected to vertical vibration experimentally. We observe that the defect can attract or repel solitons including phase-matched breather, phase-mismatched breather, and phase-mismatched kink. Furthermore, we observe a new phenomenon that the interaction polarity is dependent on the location of the defect in the phase-matched breather. If a defect locating near a breather center attracts the breather, it will repel the breather when it locates at a further place. And the effects of the defect on the phase-mismatched solitons are similar to the phenomena observed in the studies on the pendulum length defects. We also find the interaction intensity is related to the defect intensity.