Defect dynamics in complex plasmas: Interactions between solitons and penta-hepta defects (dislocations)

We report an experimental and numerical study of the dynamic behavior of dislocations in two-dimensional strongly coupled plasma crystals excited by compressional solitary waves. Complex plasmas are mixtures of micron-sized particles with ion-electron plasmas. Confined in the sheath of a gas discharge they often form hexagonal quasi-crystals. It was found that the penta-hepta defect either moved in small increments due to elastic deformation caused by the wave or experienced large jumps from one pair of particles to the next. The elastic displacement occurred primarily in the direction of the wave, whereas the jumps were in the direction parallel to Burger's vector of the dislocation. Copyright (C) EPLA, 2010