New model to calculate the vibrational lattice frequency in dust crystals using a generalized nonlinear screening potential

Summary form only given, as follows. The formation of Coulomb quasi lattices involving high charged dust grains is already demonstrated and actually is very interesting in the physics of dusty plasmas. In this paper we consider dust-crystal structures in the sheath region where a balance between gravitational and electrostatic forces levitates the particles above an horizontal biased electrode. Using a nonlinear calculation of the screening potential for no-point charges, we determine the corrected frequency of the vertical modes of oscillation of dust crystals. The use of this screening potential is more realistic than that of Debye or dressed potentials. An analysis of this frequency as a function of the plasma parameter is carried out and compared with the values obtained using previous models.