The role of positronium decoherence in the studies of positron annihilation in matter

TL;DR

This paper investigates how positronium superposition states decohere in matter, affecting the interpretation of positron annihilation lifetime spectra and suggesting corrections for more accurate analysis.

Contribution

It introduces the concept of positronium superposition decoherence and estimates its timescale, proposing corrections in data analysis methods.

Findings

Decoherence time of positronium superposition estimated

Implications for correction in positron annihilation spectra analysis

Highlights the importance of superposition effects in positronium evolution

Abstract

A small difference between the energy of the para-positronium (p-Ps) and ortho-positronium (o-Ps) states suggests the possibility of superposition of p-Ps and o-Ps during the formation of positronium (Ps) from pre-Ps terminating its migration in the matter in a void ('free volume'). It is shown that such a superposition decohere in the basis of p-Ps and o-Ps and the decoherence time is estimated. The time scale of the decoherence estimated here motivates respective correction in decomposition of the positron annihilation lifetime spectra. The way of the correction is sketched. The timescale of the decoherence suggests a need of awareness when experimental data from positron annihilation techniques are processed. More generally, the superposited state of Ps should contribute to the evolution theory of positronium in matter.