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arXiv · 1104.5441

Quantum Monte Carlo Study of a Positron in an Electron Gas

N. D. Drummond·P. Lopez Rios·C. J. Pickard·R. J. Needs
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Abstract

Quantum Monte Carlo calculations of the relaxation energy, pair-correlation function, and annihilating-pair momentum density are presented for a positron immersed in a homogeneous electron gas. We find smaller relaxation energies and contact pair-correlation functions in the important low-density regime than predicted by earlier studies. Our annihilating-pair momentum densities have almost zero weight above the Fermi momentum due to the cancellation of electron-electron and electron-positron correlation effects.

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N. D. Drummond, P. Lopez Rios, C. J. Pickard, R. J. Needs. 2011-04-28. Quantum Monte Carlo Study of a Positron in an Electron Gas. https://doi.org/10.1103/physrevlett.107.207402

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