Strongly coupled Yukawa plasma layer in a harmonic trap

Abstract

Observations made in dusty plasma experiments suggest that an ensemble of electrically charged solid particles, confined in an elongated trap, develops structural inhomogeneities. With narrowing the trap the particles tend to form layers oriented parallel with the trap walls. In this work we present theoretical and numerical results on the structure of three-dimensional many-particle systems with screened Coulomb (Yukawa) inter-particle interaction in the strongly coupled liquid phase, confined in one-dimensional harmonic trap, forming quasi-2D configurations. Particle density profiles are calculated by means of the hypernetted chain approximation (HNC), showing clear signs of layer formation. The mechanism behind the formation of layer structure is discussed and a method to predict the number of layers is presented. Molecular dynamics (MD) simulations provide validation of the theoretical results and detailed microscopic insights.