The Padé approximant technique and the variational Monte Carlo method are applied to determine the ground-state energy of a finite number of charged bosons in two dimensions confined by a parabolic trap. The particles interact repulsively through a Coulombic $1/r$ potential. Analytic expressions for the ground-state energy are obtained. The convergence of the Padé sequence and comparison with the Monte Carlo results show that the error of the Padé estimate is less than 4% at any boson density and is exact in the extreme situations of very dilute and high density.

• Received 23 June 1998

DOI:https://doi.org/10.1103/PhysRevB.59.1653