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Nonpolar optical scattering of positronium in magnesium fluoride

I. V. Bondarev·Y. Nagai·M. Kakimoto·T. Hyodo
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Abstract

We report the results of the analysis of the temperature broadening of the momentum distribution of delocalized Positronium (Ps) in Magnesium Fluoride in terms of optical deformation-potential scattering model (long-wavelength optical phonons). The Ps optical deformation-potential coupling constant $D_{o}$ in MgF$_{2}$ has been determined to be $(1.8\pm0.3)\times10^{9}$ eV/cm. We also show that the Ps momentum distribution is sensitive to second-order phase transitions in those crystals where optical deformation-potential scattering is allowed in one and forbidden in another crystalline phase.

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I. V. Bondarev, Y. Nagai, M. Kakimoto, T. Hyodo. 2004-11-23. Nonpolar optical scattering of positronium in magnesium fluoride. https://doi.org/10.1103/physrevb.72.012303

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