Interparticle Forces Between the Upper and Lower Particles in a Vertically Aligned Dust Particle Chain

Summary form only given. Complex plasmas are known to exist in a variety of natural and laboratory environments. Within an experimentally produced complex plasma such as that found in a GEC rf reference cell in a laboratory, it has been shown that dust particles often form two-, three-, or even longer particle chains, vertically aligned within the sheath. Of these, the two-particle chain remains the simplest structure. The interparticle (interlayer) interaction between upper and lower particles is of great interest and not yet completely understood. This paper discusses this interaction, providing data produced by perturbing such particle chains employing a modulated DC bias on the lower (powered) electrode. Using upper and lower particles having different masses (resulting in different charges), the resonant frequencies of each will be examined and analyzed.