Quantum efficiency measurements for long-wavelength operation of rare-earth-doped KPb/sub 2/Cl/sub 5/

Summary form only given.Host materials with low maximum phonon energies and high luminescence-quantum yields are the subject of research for long-wavelength (4-10 /spl mu/m) applications. High quantum efficiency of these devices requires low multiphonon quenching of the excited population, which is accomplished through low phonon energy hosts. We have identified KPb/sub 2/Cl/sub 5/ as a promising new host for mid-IR applications. It is moisture-resistant, incorporates rare-earth ions, and has a very low maximum-phonon frequency (200 cm/sup -1/). Direct determination of the mid-IR quantum efficiencies and decay rates is important in its evaluation.