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Symmetry breaking and the random-phase approximation in small quantum dots

Llorens Serra·Rashid G. Nazmitdinov·A. Puente
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Abstract

The random-phase approximation has been used to compute the properties of parabolic two-dimensional quantum dots beyond the mean-field approximation. Special emphasis is put on the ground state correlation energy, the symmetry restoration and the role of the spurious modes within the random-phase approximation. A systematics with the Coulombic interaction strength is presented for the 2-electron dot, while for the 6- and 12-electron dots selected cases are discussed. The validity of the random-phase approximation is assessed by comparison with available exact results.

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Llorens Serra, Rashid G. Nazmitdinov, A. Puente. 2003-08-27. Symmetry breaking and the random-phase approximation in small quantum dots. https://doi.org/10.1103/physrevb.68.035341

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