Effect of Gurevich Polarization Force on Arbitrary Amplitude Dust-Acoustic Waves and Double-Layer Structures in a Collisionless Complex Plasma

In this article, we have investigated the effect of the Gurevich polarization force on both large-amplitude dust-acoustic (DA) solitary waves and double-layer (DL) structures in a collisionless complex plasma. To do this, we have redefined the 3-D Gurevich distribution, which describes the evolution of the adiabatically trapped ions in the plasma potential well and derived the associated density and polarization force expressions. As an application, we have reviewed, using the pseudo-potential approach, the nonlinear DA solitons in an unmagnetized polarized complex plasma containing inertial dust grains, Maxwellian electrons, and adiabatically trapped ions. We have shown that the spatial profile of DA solitary waves is drastically affected by the Gurevich polarization force. In particular, we have found that due to the presence of this polarization force, the potential pulse amplitude increases while its width decreases, thus making the DA structure more spiky. For the sake of completeness, we have also analyzed the effect of the polarization force on DA-DL structures. Our numerical results have shown that both amplitude and width of rarefactive (compressive) DL DA structure decrease (increase) in the presence of polarization force.