Diffusion Monte Carlo study of circular quantum dots

Abstract

We present ground and excited state energies obtained from Diffusion Monte Carlo (DMC) calculations, using accurate multiconfiguration wave functions, for N electrons (N ≤ 13) confined to a circular quantum dot. We compare the density and correlation energies to the predictions of local spin density approximation theory (LSDA), and Hartree-Fock theory (HF), and analyze the electron-electron pair-correlation functions. The DMC estimated change in electrochemical potential as a function of the number of electrons in the dot is compared to that from LSDA and HF calculations. Hund's first rule is found to be satisfied for all dots except N = 4 for which there is a near degeneracy. 85.30.Vw,

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