Dielectric Constant of GaP at 1.6°K

A comparison of observed and calculated line positions in a donor-acceptor pair spectrum yields a value of ε(0)=10.75±0.1 for the GaP static dielectric constant at 1.6^∘{}K. Earlier analyses of pair spectra assumed ε(0)=11.1, the value obtained from Raman-scattering measurements at 300^∘{}K. The new value of ε(0) necessitates a small revision in the ionization energies of some donors and acceptors.