  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.
