title: Scaling in the correlation energies of two-dimensional artificial atoms.
abstract: We find an unexpected scaling in the correlation energy of artificial atoms, i.e., harmonically confined two-dimensional quantum dots. The scaling relation is found through extensive numerical examinations including Hartree-Fock, variational quantum Monte Carlo, density functional, and full configuration interaction calculations. We show that the correlation energy, i.e., the true ground-state total energy minus the Hartree-Fock total energy, follows a simple function of the Coulomb energy, confinement strength and number of electrons. We find an analytic expression for this function, as well as for the correlation energy per particle and for the ratio between the correlation and total energies. Our tests for independent diffusion Monte Carlo and coupled-cluster results for quantum dots-including open-shell data-confirm the generality of the scaling obtained. As the scaling also applies well to ≳100 electrons, our results give interesting prospects for the development of correlation functionals within density functional theory.
authors.affiliation: COMP Centre of Excellence, Department of Applied Physics, Aalto University School of Science, PO Box 11100, FI-00076 AALTO, Espoo, Finland. Department of Physics, Tampere University of Technology, FI-33101 Tampere, Finland. Helsinki Institute of Physics, Aalto University, PO Box 11100, FI-00076 AALTO, Espoo, Finland.
authors.forename: Alexander
authors.initials: A
authors.lastname: Odriazola
authors.forename: Mikko M
authors.initials: MM
authors.lastname: Ervasti
authors.forename: Ilja
authors.initials: I
authors.lastname: Makkonen
authors.forename: Alain
authors.initials: A
authors.lastname: Delgado
authors.forename: Augusto
authors.initials: A
authors.lastname: González
authors.forename: Esa
authors.initials: E
authors.lastname: Räsänen
authors.forename: Ari
authors.initials: A
authors.lastname: Harju
mesh_terms: D003198:Computer Simulation; D004583:Electrons; D008956:Models, Chemical; D009010:Monte Carlo Method; D011789:Quantum Theory