The dependence of microwave conductivity, σ_(MW), on temperature (T) and alkali concentration has been studied for potassium germanate glass of composition Xk_2O·(1-x)GeO_2, 0.0023≤ x ≤ 0.247. From the empirical analysis, it is established that conduction at high frequency (f) and high T in these glasses is related to the conduction at low f and low T. The temperature dependence of σ_(MW) shows a weak thermal activation for all compositions as predicted by the model of jellyfish-like localized fluctuations of atoms in asymmetric double well potential configurations (ADWPC). The variation of σ_(MW) with alkali oxide concentration is however weaker than that observed at low T. It increases only by a factor of 2 for an increase from 0.23 to 25 mol% of K_2O at 1GHz.
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