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Quantum Monte Carlo study of a positron in an electron gas
N D Drummond1, P López Ríos, R J Needs
1Department of Physics, Lancaster University, United Kingdom.
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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