Ytterbium, atomic no. 70, symbol Yb, weight at 173.04, is being applied to numerous fiber amplifier and fiber optic technologies and in various lasing applications. It has a single dominant absorption band at 985 in the infra-red making it useful in silicon photocells to directly convert radiant energy to electricity.
Ytterbium metal increases its electrical resistance when subjected to very high stresses. This property is used in stress gauges for monitoring ground deformations from earthquakes and nuclear explosions.
It is also used as in thermal barrier system bond coatings on nickel, iron and other transitional metal alloy substrates.