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arXiv · 2202.13204

Quantum Monte Carlo study of positron lifetimes in solids

K. A. Simula·J. E. Muff·I. Makkonen·N. D. Drummond
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Abstract

We present an analysis of positron lifetimes in solids with unprecedented depth. Instead of modeling correlation effects with density functionals, we study positron-electron wave functions with long-range correlations included. This gives new insight in understanding positron annihilation in metals, insulators and semiconductors. By using a new quantum Monte Carlo approach for computation of positron lifetimes, an improved accuracy compared to previous computations is obtained for a representative set of materials when compared with experiment. Thus we present a method without free parameters as a useful alternative to the already existing methods for modeling positrons in solids.

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K. A. Simula, J. E. Muff, I. Makkonen, N. D. Drummond. 2022-02-26. Quantum Monte Carlo study of positron lifetimes in solids. https://doi.org/10.1103/physrevlett.129.166403

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