Electronic properties in quantum dots with asymmetric confining potential

N-electron eigenstates in circular, elliptical and triangular quantum dots are calculated by numerically diagonalizing the N-electron Hamiltonian. The addition energy spectrum for a circular quantum dot shows good agreement with the experimental results reported by Tarucha et al. In elliptical quantum dots, the degeneracy of the single-particle states is removed, resulting in a transition of the ground state for a quantum dot with four electrons from the Spin-polarized half-filled configuration to the spin-singlet state. The states with 3, 6 and 9 electrons in a triangular quantum dot are found to be slightly more stable compared with a circular quantum dot, which is interpreted in terms of a geometrical effect.